Fetcher: avoid response deadlock (#975)

* DiskV2: avoid allocating zero chunk on each zeroSkippingWrite() call

* Increase hole granularity size from 64 KiB to 4 MiB

* Fetcher: never write to disk, thanks to URLSessionDataDelegate

.ci/set-version.sh

@@ -3,3 +3,5 @@
 TMPFILE=$(mktemp)
 envsubst < Sources/tart/CI/CI.swift > $TMPFILE
 mv $TMPFILE Sources/tart/CI/CI.swift
+
+/usr/libexec/PlistBuddy -c "Add :CFBundleShortVersionString string ${CIRRUS_TAG}" Resources/Info.plist

PROFILING.md

@@ -0,0 +1,64 @@
+# Profiling Tart
+
+## Using `time(1)`
+
+Perhaps, the easiest, but not the most comprehensive way to tell what's going on with Tart is to use the [`time(1)`](https://ss64.com/mac/time.html) command.
+
+In the example below, you will run `tart pull` via `time(1)` to gather generalized CPU, I/O and memory usage metrics:
+
+```shell
+/usr/bin/time -l tart pull ghcr.io/cirruslabs/macos-sequoia-base:latest
+```
+
+**Note:** you need to specify a full path to `time(1)` binary, otherwise the shell's built-in `time` command will be invoked, which doesn't have the `-l` command-line argument.
+
+**Note:** The `-l` command-line argument makes `time(1)` return much more useful information, for example, maximum memory usage.
+
+When running the command above, you'll see the `tart pull` output first as it pulls the image, and then the `time(1)` output, which will be printed once the Tart process finishes:
+
+```
+      172.17 real        10.29 user         8.36 sys
+           353796096  maximum resident set size
+                   0  average shared memory size
+                   0  average unshared data size
+                   0  average unshared stack size
+               23838  page reclaims
+                  35  page faults
+                   0  swaps
+                   0  block input operations
+                   0  block output operations
+                   8  messages sent
+                   8  messages received
+                   0  signals received
+                 146  voluntary context switches
+              222950  involuntary context switches
+         39683070975  instructions retired
+         27562035252  cycles elapsed
+           170920448  peak memory footprint
+```
+
+From the output above, you can tell that `tart pull` spent nearly 90% of time off-CPU (`real` > `user` + `sys`), which means that Tart was mostly waiting for the I/O (be it a network or disk), instead of decompressing disk layers or doing other useful computations.
+
+## Using `xctrace(1)`
+
+[`xctrace(1)`](https://keith.github.io/xcode-man-pages/xctrace.1.html) is a `.trace` format recorder for the [Instruments](https://en.wikipedia.org/wiki/Instruments_(software)) app, which yields much more powerful insights compared to `time(1)`. For example, it can tell which Tart functions spent the most time on the CPU, thus allowing the Tart developers to further optimize these functions.
+
+To use it, make sure that [Xcode](https://developer.apple.com/xcode/resources/) is installed. If you're installing Xcode for the first time on the machine, you'll need to launch it once and click the blue "Install" button. There's no need to choose any platforms except for the macOS.
+
+Once done, you can create a CPU profile of `tart pull`:
+
+```shell
+xctrace record --template "CPU Profiler" --target-stdout - --launch -- /opt/homebrew/bin/tart pull ghcr.io/cirruslabs/macos-sequoia-base:latest
+```
+
+Now that `xctrace(1)` is running, you'll see the `tart pull`-related output first, and once finished, the following line will appear:
+
+```
+Output file saved as: Launch_[...].trace
+```
+
+To view this trace in the Instruments app, simply find this directory in Finder and double-click it. Instruments app will appear:
+
+![](Resources/Instruments.png)
+
+To send this trace, right-click its directory in Finder and choose "Compress [...]". This will result in a similarly named file with a `.zip` at the end, which can now be conveniently sent via email or uploaded.

Package.resolved

@@ -1,13 +1,13 @@
 {
-  "originHash" : "2c514a4a1d7e106713db744bee89edb40d75da63e6611990ec2f4b0da53c0455",
+  "originHash" : "22b3726bc4e4c6e9c04ac97cb08a82967feb39960a93d2909768a16e11576748",
   "pins" : [
     {
       "identity" : "antlr4",
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/antlr/antlr4",
       "state" : {
-        "branch" : "dev",
-        "revision" : "2703a8516c0fb7fe92db6b9c40e0113f577646d2"
+        "revision" : "cc82115a4e7f53d71d9d905caa2c2dfa4da58899",
+        "version" : "4.13.2"
       }
     },
     {
@@ -24,8 +24,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/groue/Semaphore",
       "state" : {
-        "revision" : "f1c4a0acabeb591068dea6cffdd39660b86dec28",
-        "version" : "0.0.8"
+        "revision" : "2543679282aa6f6c8ecf2138acd613ed20790bc2",
+        "version" : "0.1.0"
       }
     },
     {
@@ -33,8 +33,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/getsentry/sentry-cocoa",
       "state" : {
-        "revision" : "ef4fec9dfb8dd5027b09a4a5c9362feafd118e1a",
-        "version" : "8.24.0"
+        "revision" : "5575af93efb776414f243e93d6af9f6258dc539a",
+        "version" : "8.36.0"
       }
     },
     {
@@ -51,17 +51,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/apple/swift-argument-parser",
       "state" : {
-        "revision" : "46989693916f56d1186bd59ac15124caef896560",
-        "version" : "1.3.1"
-      }
-    },
-    {
-      "identity" : "swift-async-algorithms",
-      "kind" : "remoteSourceControl",
-      "location" : "https://github.com/apple/swift-async-algorithms",
-      "state" : {
-        "branch" : "main",
-        "revision" : "f05e450f0b909c0e80670a47516c4b9700b9e5da"
+        "revision" : "41982a3656a71c768319979febd796c6fd111d5c",
+        "version" : "1.5.0"
       }
     },
     {
@@ -73,22 +64,13 @@
         "version" : "1.2.0"
       }
     },
-    {
-      "identity" : "swift-collections",
-      "kind" : "remoteSourceControl",
-      "location" : "https://github.com/apple/swift-collections.git",
-      "state" : {
-        "revision" : "f504716c27d2e5d4144fa4794b12129301d17729",
-        "version" : "1.0.3"
-      }
-    },
     {
       "identity" : "swift-log",
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/apple/swift-log.git",
       "state" : {
-        "revision" : "e97a6fcb1ab07462881ac165fdbb37f067e205d5",
-        "version" : "1.5.4"
+        "revision" : "9cb486020ebf03bfa5b5df985387a14a98744537",
+        "version" : "1.6.1"
       }
     },
     {
@@ -105,8 +87,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/fumoboy007/swift-retry",
       "state" : {
-        "revision" : "9f133487ffc2ab4539688c29efe57bb1ba31d7b0",
-        "version" : "0.2.3"
+        "revision" : "df9d7b185d2e433147ec0083a73c257e665eea0d",
+        "version" : "0.2.4"
       }
     },
     {
@@ -141,8 +123,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/nicklockwood/SwiftFormat",
       "state" : {
-        "revision" : "9df3b01f477163b33d5e63c5e2e5b9f946a49c56",
-        "version" : "0.53.6"
+        "revision" : "ab6844edb79a7b88dc6320e6cee0a0db7674dac3",
+        "version" : "0.54.5"
       }
     },
     {

Package.swift

@@ -13,12 +13,11 @@ let package = Package(
     .package(url: "https://github.com/apple/swift-argument-parser", from: "1.3.1"),
     .package(url: "https://github.com/mhdhejazi/Dynamic", branch: "master"),
     .package(url: "https://github.com/apple/swift-algorithms", from: "1.2.0"),
-    .package(url: "https://github.com/apple/swift-async-algorithms", branch: "main"),
     .package(url: "https://github.com/malcommac/SwiftDate", from: "7.0.0"),
-    .package(url: "https://github.com/antlr/antlr4", branch: "dev"),
+    .package(url: "https://github.com/antlr/antlr4", exact: "4.13.2"),
     .package(url: "https://github.com/apple/swift-atomics.git", .upToNextMajor(from: "1.2.0")),
     .package(url: "https://github.com/nicklockwood/SwiftFormat", from: "0.53.6"),
-    .package(url: "https://github.com/getsentry/sentry-cocoa", from: "8.24.0"),
+    .package(url: "https://github.com/getsentry/sentry-cocoa", from: "8.36.0"),
     .package(url: "https://github.com/cfilipov/TextTable", branch: "master"),
     .package(url: "https://github.com/sersoft-gmbh/swift-sysctl.git", from: "1.8.0"),
     .package(url: "https://github.com/orchetect/SwiftRadix", from: "1.3.1"),
@@ -29,7 +28,6 @@ let package = Package(
   targets: [
     .executableTarget(name: "tart", dependencies: [
       .product(name: "Algorithms", package: "swift-algorithms"),
-      .product(name: "AsyncAlgorithms", package: "swift-async-algorithms"),
       .product(name: "ArgumentParser", package: "swift-argument-parser"),
       .product(name: "Dynamic", package: "Dynamic"),
       .product(name: "SwiftDate", package: "SwiftDate"),

Resources/Info.plist

@@ -2,22 +2,24 @@
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
 <dict>
-    <key>CFBundleName</key>
-    <string>tart</string>
-    <key>CFBundleIdentifier</key>
-    <string>org.cirruslabs.tart</string>
-    <key>CFBundleExecutable</key>
-    <string>tart</string>
-    <key>LSBackgroundOnly</key>
-    <string>1</string>
-    <key>CFBundleIconFiles</key>
-    <array>
-        <string>AppIcon.png</string>
-    </array>
-    <key>NSAppTransportSecurity</key>
-    <dict>
-        <key>NSAllowsArbitraryLoads</key>
-        <true/>
-    </dict>
+	<key>CFBundleName</key>
+	<string>Tart</string>
+	<key>CFBundleDisplayName</key>
+	<string>Tart</string>
+	<key>CFBundleIdentifier</key>
+	<string>org.cirruslabs.tart</string>
+	<key>CFBundleExecutable</key>
+	<string>tart</string>
+  <key>LSApplicationCategoryType</key>
+  <string>public.app-category.developer-tools</string>
+	<key>CFBundleIconFiles</key>
+	<array>
+		<string>AppIcon.png</string>
+	</array>
+	<key>NSAppTransportSecurity</key>
+	<dict>
+		<key>NSAllowsArbitraryLoads</key>
+		<true/>
+	</dict>
 </dict>
 </plist>

Sources/tart/Commands/Clone.swift

@@ -9,12 +9,10 @@ struct Clone: AsyncParsableCommand {
     Creates a local virtual machine by cloning either a remote or another local virtual machine.
 
     Due to copy-on-write magic in Apple File System, a cloned VM won't actually claim all the space right away.
-    Only changes to a cloned disk will be written and claim new space. By default, Tart checks available capacity
-    in Tart's home directory and checks if there is enough space for the worst possible scenario: when the whole disk
-    will be modified.
+    Only changes to a cloned disk will be written and claim new space. This also speeds up clones enormously.
 
-    This behaviour can be disabled by setting TART_NO_AUTO_PRUNE environment variable. This might be helpful
-    for use cases when the original image is very big and a workload is known to only modify a fraction of the cloned disk.
+    By default, Tart checks available capacity in Tart's home directory and tries to reclaim minimum possible storage for the cloned image
+    to fit. This behaviour is called "automatic pruning" and can be disabled by setting TART_NO_AUTO_PRUNE environment variable.
     """
   )
 
@@ -30,6 +28,9 @@ struct Clone: AsyncParsableCommand {
   @Option(help: "network concurrency to use when pulling a remote VM from the OCI-compatible registry")
   var concurrency: UInt = 4
 
+  @Flag(help: .hidden)
+  var deduplicate: Bool = false
+
   func validate() throws {
     if newName.contains("/") {
       throw ValidationError("<new-name> should be a local name")
@@ -47,7 +48,7 @@ struct Clone: AsyncParsableCommand {
     if let remoteName = try? RemoteName(sourceName), !ociStorage.exists(remoteName) {
       // Pull the VM in case it's OCI-based and doesn't exist locally yet
       let registry = try Registry(host: remoteName.host, namespace: remoteName.namespace, insecure: insecure)
-      try await ociStorage.pull(remoteName, registry: registry, concurrency: concurrency)
+      try await ociStorage.pull(remoteName, registry: registry, concurrency: concurrency, deduplicate: deduplicate)
     }
 
     let sourceVM = try VMStorageHelper.open(sourceName)
@@ -70,10 +71,14 @@ struct Clone: AsyncParsableCommand {
 
       try lock.unlock()
 
-      // APFS is doing copy-on-write so the above cloning operation (just copying files on disk)
+      // APFS is doing copy-on-write, so the above cloning operation (just copying files on disk)
       // is not actually claiming new space until the VM is started and it writes something to disk.
-      // So once we clone the VM let's try to claim a little bit of space for the VM to run.
-      try Prune.reclaimIfNeeded(UInt64(sourceVM.allocatedSizeBytes()), sourceVM)
+      //
+      // So, once we clone the VM let's try to claim the rest of space for the VM to run without errors.
+      let unallocatedBytes = try sourceVM.sizeBytes() - sourceVM.allocatedSizeBytes()
+      if unallocatedBytes > 0 {
+        try Prune.reclaimIfNeeded(UInt64(unallocatedBytes), sourceVM)
+      }
     }, onCancel: {
       try? FileManager.default.removeItem(at: tmpVMDir.baseURL)
     })

Sources/tart/Commands/Pull.swift

@@ -9,8 +9,8 @@ struct Pull: AsyncParsableCommand {
     Pulls a virtual machine from a remote OCI-compatible registry. Supports authorization via Keychain (see "tart login --help"),
     Docker credential helpers defined in ~/.docker/config.json or via TART_REGISTRY_USERNAME/TART_REGISTRY_PASSWORD environment variables.
 
-    By default, Tart checks available capacity in Tart's home directory and tries to reclaim minimum possible storage for the remote image to fit via "tart prune".
-    This behaviour can be disabled by setting TART_NO_AUTO_PRUNE environment variable.
+    By default, Tart checks available capacity in Tart's home directory and tries to reclaim minimum possible storage for the remote image
+    to fit. This behaviour is called "automatic pruning" and can be disabled by setting TART_NO_AUTO_PRUNE environment variable.
     """
   )
 
@@ -23,6 +23,9 @@ struct Pull: AsyncParsableCommand {
   @Option(help: "network concurrency to use when pulling a remote VM from the OCI-compatible registry")
   var concurrency: UInt = 4
 
+  @Flag(help: .hidden)
+  var deduplicate: Bool = false
+
   func validate() throws {
     if concurrency < 1 {
       throw ValidationError("network concurrency cannot be less than 1")
@@ -43,6 +46,6 @@ struct Pull: AsyncParsableCommand {
 
     defaultLogger.appendNewLine("pulling \(remoteName)...")
 
-    try await VMStorageOCI().pull(remoteName, registry: registry, concurrency: concurrency)
+    try await VMStorageOCI().pull(remoteName, registry: registry, concurrency: concurrency, deduplicate: deduplicate)
   }
 }

Sources/tart/Commands/Run.swift

@@ -45,6 +45,23 @@ extension VZDiskImageSynchronizationMode {
   }
 }
 
+extension VZDiskImageCachingMode {
+  public init?(_ description: String) throws {
+    switch description {
+    case "automatic":
+      self = .automatic
+    case "cached":
+      self = .cached
+    case "uncached":
+      self = .uncached
+    case "":
+      return nil
+    default:
+      throw RuntimeError.VMConfigurationError("unsupported disk image caching mode: \"\(description)\"")
+    }
+  }
+}
+
 struct Run: AsyncParsableCommand {
   static var configuration = CommandConfiguration(abstract: "Run a VM")
 
@@ -156,6 +173,9 @@ struct Run: AsyncParsableCommand {
   """, valueName: "[name:]path[:options]"))
   var dir: [String] = []
 
+  @Flag(help: ArgumentHelp("Enable nested virtualization if possible"))
+  var nested: Bool = false
+
   @Option(help: ArgumentHelp("""
   Use bridged networking instead of the default shared (NAT) networking \n(e.g. --net-bridged=en0 or --net-bridged=\"Wi-Fi\")
   """, discussion: """
@@ -173,7 +193,7 @@ struct Run: AsyncParsableCommand {
   @Flag(help: ArgumentHelp("Restrict network access to the host-only network"))
   var netHost: Bool = false
 
-  @Option(help: ArgumentHelp("Set the root disk options (e.g. --root-disk-opts=\"ro\" or --root-disk-opts=\"sync=none\")",
+  @Option(help: ArgumentHelp("Set the root disk options (e.g. --root-disk-opts=\"ro\" or --root-disk-opts=\"caching=cached,sync=none\")",
                              discussion: """
                              Options are comma-separated and are as follows:
 
@@ -184,6 +204,12 @@ struct Run: AsyncParsableCommand {
                              * sync=fsync — enable data synchronization with the permanent storage, but don't ensure that it was actually written (e.g. --root-disk-opts="sync=fsync")
 
                              * sync=full — enable data synchronization with the permanent storage and ensure that it was actually written (e.g. --root-disk-opts="sync=full")
+
+                             * caching=automatic — allows the virtualization framework to automatically determine whether to enable data caching
+
+                             * caching=cached — enabled data caching
+
+                             * caching=uncached — disables data caching
                              """, valueName: "options"))
   var rootDiskOpts: String = ""
 
@@ -221,6 +247,14 @@ struct Run: AsyncParsableCommand {
       throw ValidationError("--captures-system-keys can only be used with the default VM view")
     }
 
+    if nested {
+      if #unavailable(macOS 15) {
+        throw ValidationError("Nested virtualization is supported on hosts starting with macOS 15 (Sequia), and later.")
+      } else if !VZGenericPlatformConfiguration.isNestedVirtualizationSupported {
+        throw ValidationError("Nested virtualization is available for Mac with the M3 chip, and later.")
+      }
+    }
+
     let localStorage = VMStorageLocal()
     let vmDir = try localStorage.open(name)
     if try vmDir.state() == .Suspended {
@@ -294,9 +328,11 @@ struct Run: AsyncParsableCommand {
       directorySharingDevices: directoryShares() + rosettaDirectoryShare(),
       serialPorts: serialPorts,
       suspendable: suspendable,
+      nested: nested,
       audio: !noAudio,
       clipboard: !noClipboard,
-      sync: VZDiskImageSynchronizationMode(diskOptions.syncModeRaw)
+      sync: VZDiskImageSynchronizationMode(diskOptions.syncModeRaw),
+      caching: VZDiskImageCachingMode(diskOptions.cachingModeRaw)
     )
 
     let vncImpl: VNC? = try {
@@ -346,7 +382,35 @@ struct Run: AsyncParsableCommand {
           }
         #endif
 
-        try await vm!.start(recovery: recovery, resume: resume)
+        do {
+          try await vm!.start(recovery: recovery, resume: resume)
+        } catch let error as VZError {
+          if error.code == .virtualMachineLimitExceeded {
+            var hint = ""
+
+            do {
+              let runningVMs: [String] = try localStorage.list().compactMap { (name, vmDir) in
+                if try !vmDir.running() {
+                  return nil
+                }
+
+                return name
+              }
+
+              if !runningVMs.isEmpty {
+                let runningVMsJoined = runningVMs.joined(separator: ", ")
+
+                hint = " (other running VMs: \(runningVMsJoined))"
+              }
+            } catch {
+              // we can't provide any hint
+            }
+
+            throw RuntimeError.VirtualMachineLimitExceeded(hint)
+          }
+
+          throw error
+        }
 
         if let vncImpl = vncImpl {
           let vncURL = try await vncImpl.waitForURL(netBridged: !netBridged.isEmpty)
@@ -432,8 +496,10 @@ struct Run: AsyncParsableCommand {
 
     let useVNCWithoutGraphics = (vnc || vncExperimental) && !graphics
     if noGraphics || useVNCWithoutGraphics {
-      // enter the main even loop, without bringing up any UI,
-      // and just wait for the VM to exit.
+      // Enter the main event loop without bringing up any UI,
+      // waiting for the VM to exit.
+      NSApplication.shared.setActivationPolicy(.prohibited)
+
       NSApplication.shared.run()
     } else {
       runUI(suspendable, captureSystemKeys)
@@ -589,7 +655,7 @@ struct MainApp: App {
   static var suspendable: Bool = false
   static var capturesSystemKeys: Bool = false
 
-  @NSApplicationDelegateAdaptor private var appDelegate: MinimalMenuAppDelegate
+  @NSApplicationDelegateAdaptor private var appDelegate: AppDelegate
 
   var body: some Scene {
     WindowGroup(vm!.name) {
@@ -645,18 +711,7 @@ struct MainApp: App {
   }
 }
 
-// The only way to fully remove Edit menu item.
-class MinimalMenuAppDelegate: NSObject, NSApplicationDelegate, ObservableObject {
-  let indexOfEditMenu = 2
-
-  func applicationDidFinishLaunching(_ : Notification) {
-    NSApplication.shared.mainMenu?.removeItem(at: indexOfEditMenu)
-
-    let nsApp = NSApplication.shared
-    nsApp.setActivationPolicy(.regular)
-    nsApp.activate(ignoringOtherApps: true)
-  }
-
+class AppDelegate: NSObject, NSApplicationDelegate, ObservableObject {
   func applicationShouldTerminate(_ sender: NSApplication) -> NSApplication.TerminateReply {
     if (kill(getpid(), MainApp.suspendable ? SIGUSR1 : SIGINT) == 0) {
       return .terminateLater
@@ -709,12 +764,12 @@ struct VMView: NSViewRepresentable {
 
     machineView.capturesSystemKeys = capturesSystemKeys
 
-    // Enable automatic display reconfiguration
-    // for guests that support it
+    // If not specified, enable automatic display
+    // reconfiguration for guests that support it
     //
     // This is disabled for Linux because of poor HiDPI
     // support, which manifests in fonts being too small
-    if #available(macOS 14.0, *), vm.config.os != .linux {
+    if #available(macOS 14.0, *), vm.config.displayRefit ?? (vm.config.os != .linux) {
       machineView.automaticallyReconfiguresDisplay = true
     }
 
@@ -730,12 +785,12 @@ struct AdditionalDisk {
   let configuration: VZStorageDeviceConfiguration
 
   init(parseFrom: String) throws {
-    let (diskPath, readOnly, syncModeRaw) = Self.parseOptions(parseFrom)
+    let (diskPath, readOnly, syncModeRaw, cachingModeRaw) = Self.parseOptions(parseFrom)
 
-    self.configuration = try Self.craft(diskPath, readOnly: readOnly, syncModeRaw: syncModeRaw)
+    self.configuration = try Self.craft(diskPath, readOnly: readOnly, syncModeRaw: syncModeRaw, cachingModeRaw: cachingModeRaw)
   }
 
-  static func craft(_ diskPath: String, readOnly diskReadOnly: Bool, syncModeRaw: String) throws -> VZStorageDeviceConfiguration {
+  static func craft(_ diskPath: String, readOnly diskReadOnly: Bool, syncModeRaw: String, cachingModeRaw: String) throws -> VZStorageDeviceConfiguration {
     let diskURL = URL(string: diskPath)
 
     if (["nbd", "nbds", "nbd+unix", "nbds+unix"].contains(diskURL?.scheme)) {
@@ -812,14 +867,14 @@ struct AdditionalDisk {
     let diskImageAttachment = try VZDiskImageStorageDeviceAttachment(
       url: diskFileURL,
       readOnly: diskReadOnly,
-      cachingMode: .automatic,
+      cachingMode: try VZDiskImageCachingMode(cachingModeRaw) ?? .automatic,
       synchronizationMode: try VZDiskImageSynchronizationMode(syncModeRaw)
     )
 
     return VZVirtioBlockDeviceConfiguration(attachment: diskImageAttachment)
   }
 
-  static func parseOptions(_ parseFrom: String) -> (String, Bool, String) {
+  static func parseOptions(_ parseFrom: String) -> (String, Bool, String, String) {
     var arguments = parseFrom.split(separator: ":")
 
     let options = DiskOptions(String(arguments.last!))
@@ -827,13 +882,14 @@ struct AdditionalDisk {
       arguments.removeLast()
     }
 
-    return (arguments.joined(separator: ":"), options.readOnly, options.syncModeRaw)
+    return (arguments.joined(separator: ":"), options.readOnly, options.syncModeRaw, options.cachingModeRaw)
   }
 }
 
 struct DiskOptions {
   var readOnly: Bool = false
   var syncModeRaw: String = ""
+  var cachingModeRaw: String = ""
   var foundAtLeastOneOption: Bool = false
 
   init(_ parseFrom: String) {
@@ -847,6 +903,9 @@ struct DiskOptions {
       case option.hasPrefix("sync="):
         self.syncModeRaw = String(option.dropFirst("sync=".count))
         self.foundAtLeastOneOption = true
+      case option.hasPrefix("caching="):
+        self.cachingModeRaw = String(option.dropFirst("caching=".count))
+        self.foundAtLeastOneOption = true
       default:
         continue
       }

Sources/tart/Commands/Set.swift

@@ -17,6 +17,9 @@ struct Set: AsyncParsableCommand {
   @Option(help: "VM display resolution in a format of <width>x<height>. For example, 1200x800")
   var display: VMDisplayConfig?
 
+  @Flag(inversion: .prefixedNo, help: ArgumentHelp("Whether to automatically reconfigure the VM's display to fit the window"))
+  var displayRefit: Bool? = nil
+
   @Flag(help: ArgumentHelp("Generate a new random MAC address for the VM."))
   var randomMAC: Bool = false
 
@@ -63,6 +66,8 @@ struct Set: AsyncParsableCommand {
       }
     }
 
+    vmConfig.displayRefit = displayRefit
+
     if randomMAC {
       vmConfig.macAddress = VZMACAddress.randomLocallyAdministered()
     }

Sources/tart/Credentials/DockerConfigCredentialsProvider.swift

@@ -39,9 +39,10 @@ class DockerConfigCredentialsProvider: CredentialsProvider {
     inPipe.fileHandleForWriting.write("\(host)\n".data(using: .utf8)!)
     inPipe.fileHandleForWriting.closeFile()
 
+    let outputData = try outPipe.fileHandleForReading.readToEnd()
+
     process.waitUntilExit()
 
-    let outputData = try outPipe.fileHandleForReading.readToEnd()
     if !(process.terminationReason == .exit && process.terminationStatus == 0) {
       if let outputData = outputData {
         print(String(decoding: outputData, as: UTF8.self))

Sources/tart/Fetcher.swift

@@ -1,69 +1,6 @@
 import Foundation
-import AsyncAlgorithms
 
-fileprivate let urlSession = createURLSession()
-
-class DownloadDelegate: NSObject, URLSessionTaskDelegate {
-  let progress: Progress
-  init(_ progress: Progress) throws {
-    self.progress = progress
-  }
-
-  func urlSession(_ session: URLSession, didCreateTask task: URLSessionTask) {
-    self.progress.addChild(task.progress, withPendingUnitCount: self.progress.totalUnitCount)
-  }
-}
-
-class Fetcher {
-  static func fetch(_ request: URLRequest, viaFile: Bool = false, progress: Progress? = nil) async throws -> (AsyncThrowingChannel<Data, Error>, HTTPURLResponse) {
-    let delegate = progress != nil ? try DownloadDelegate(progress!) : nil
-
-    if viaFile {
-      return try await fetchViaFile(request, delegate: delegate)
-    }
-
-    return try await fetchViaMemory(request, delegate: delegate)
-  }
-
-  private static func fetchViaMemory(_ request: URLRequest, delegate: URLSessionTaskDelegate? = nil) async throws -> (AsyncThrowingChannel<Data, Error>, HTTPURLResponse) {
-    let dataCh = AsyncThrowingChannel<Data, Error>()
-
-    let (data, response) = try await urlSession.data(for: request, delegate: delegate)
-
-    Task {
-      await dataCh.send(data)
-
-      dataCh.finish()
-    }
-
-    return (dataCh, response as! HTTPURLResponse)
-  }
-
-  private static func fetchViaFile(_ request: URLRequest, delegate: URLSessionTaskDelegate? = nil) async throws -> (AsyncThrowingChannel<Data, Error>, HTTPURLResponse) {
-    let dataCh = AsyncThrowingChannel<Data, Error>()
-
-    let (fileURL, response) = try await urlSession.download(for: request, delegate: delegate)
-
-    // Acquire a handle to the downloaded file and then remove it.
-    //
-    // This keeps a working reference to that file, yet we don't
-    // have to deal with the cleanup any more.
-    let mappedFile = try Data(contentsOf: fileURL, options: [.alwaysMapped])
-    try FileManager.default.removeItem(at: fileURL)
-
-    Task {
-      for chunk in (0 ..< mappedFile.count).chunks(ofCount: 64 * 1024 * 1024) {
-        await dataCh.send(mappedFile.subdata(in: chunk))
-      }
-
-      dataCh.finish()
-    }
-
-    return (dataCh, response as! HTTPURLResponse)
-  }
-}
-
-fileprivate func createURLSession() -> URLSession {
+fileprivate var urlSessionConfiguration: URLSessionConfiguration {
   let config = URLSessionConfiguration.default
 
   // Harbor expects a CSRF token to be present if the HTTP client
@@ -76,5 +13,84 @@ fileprivate func createURLSession() -> URLSession {
   // [2]: https://github.com/cirruslabs/tart/issues/295
   config.httpShouldSetCookies = false
 
-  return URLSession(configuration: config)
+  return config
+}
+
+class Fetcher {
+  static func fetch(_ request: URLRequest, viaFile: Bool = false, progress: Progress? = nil) async throws -> (AsyncThrowingStream<Data, Error>, HTTPURLResponse) {
+    let delegate = Delegate()
+    let session = URLSession(configuration: urlSessionConfiguration, delegate: delegate, delegateQueue: nil)
+    let task = session.dataTask(with: request)
+
+    let stream = AsyncThrowingStream<Data, Error> { continuation in
+      delegate.streamContinuation = continuation
+    }
+
+    let response = try await withCheckedThrowingContinuation { continuation in
+      delegate.responseContinuation = continuation
+      task.resume()
+    }
+
+    return (stream, response as! HTTPURLResponse)
+  }
+}
+
+fileprivate class Delegate: NSObject, URLSessionDataDelegate {
+  var responseContinuation: CheckedContinuation<URLResponse, Error>?
+  var streamContinuation: AsyncThrowingStream<Data, Error>.Continuation?
+
+  private var buffer: Data = Data()
+  private let bufferFlushSize = 16 * 1024 * 1024
+
+  func urlSession(
+    _ session: URLSession,
+    dataTask: URLSessionDataTask,
+    didReceive response: URLResponse,
+    completionHandler: @escaping (URLSession.ResponseDisposition) -> Void
+  ) {
+    // Soft-limit for the maximum buffer capacity
+    let capacity = min(response.expectedContentLength, Int64(bufferFlushSize))
+
+    // Pre-initialize buffer as we now know the capacity
+    buffer = Data(capacity: Int(capacity))
+
+    responseContinuation?.resume(returning: response)
+    responseContinuation = nil
+    completionHandler(.allow)
+  }
+
+  func urlSession(
+    _ session: URLSession,
+    dataTask: URLSessionDataTask,
+    didReceive data: Data
+  ) {
+    buffer.append(data)
+
+    if buffer.count >= bufferFlushSize {
+      streamContinuation?.yield(buffer)
+      buffer.removeAll(keepingCapacity: true)
+    }
+  }
+
+  func urlSession(
+    _ session: URLSession,
+    task: URLSessionTask,
+    didCompleteWithError error: Error?
+  ) {
+    if let error = error {
+      responseContinuation?.resume(throwing: error)
+      responseContinuation = nil
+
+      streamContinuation?.finish(throwing: error)
+      streamContinuation = nil
+    } else {
+      if !buffer.isEmpty {
+        streamContinuation?.yield(buffer)
+        buffer.removeAll(keepingCapacity: true)
+      }
+
+      streamContinuation?.finish()
+      streamContinuation = nil
+    }
+  }
 }

Sources/tart/MACAddressResolver/ARPCache.swift

@@ -52,6 +52,11 @@ struct ARPCache {
     process.standardInput = FileHandle.nullDevice
 
     try process.run()
+
+    guard let arpCommandOutput = try pipe.fileHandleForReading.readToEnd() else {
+      throw ARPCommandYieldedInvalidOutputError(explanation: "empty output")
+    }
+
     process.waitUntilExit()
 
     if !(process.terminationReason == .exit && process.terminationStatus == 0) {
@@ -60,10 +65,6 @@ struct ARPCache {
         terminationStatus: process.terminationStatus)
     }
 
-    guard let arpCommandOutput = try pipe.fileHandleForReading.readToEnd() else {
-      throw ARPCommandYieldedInvalidOutputError(explanation: "empty output")
-    }
-
     self.arpCommandOutput = arpCommandOutput
   }
 

Sources/tart/OCI/Layerizer/Disk.swift

@@ -2,5 +2,5 @@ import Foundation
 
 protocol Disk {
   static func push(diskURL: URL, registry: Registry, chunkSizeMb: Int, concurrency: UInt, progress: Progress) async throws -> [OCIManifestLayer]
-  static func pull(registry: Registry, diskLayers: [OCIManifestLayer], diskURL: URL, concurrency: UInt, progress: Progress, localLayerCache: LocalLayerCache?) async throws
+  static func pull(registry: Registry, diskLayers: [OCIManifestLayer], diskURL: URL, concurrency: UInt, progress: Progress, localLayerCache: LocalLayerCache?, deduplicate: Bool) async throws
 }

Sources/tart/OCI/Layerizer/DiskV1.swift

@@ -45,7 +45,7 @@ class DiskV1: Disk {
     return pushedLayers
   }
 
-  static func pull(registry: Registry, diskLayers: [OCIManifestLayer], diskURL: URL, concurrency: UInt, progress: Progress, localLayerCache: LocalLayerCache? = nil) async throws {
+  static func pull(registry: Registry, diskLayers: [OCIManifestLayer], diskURL: URL, concurrency: UInt, progress: Progress, localLayerCache: LocalLayerCache? = nil, deduplicate: Bool = false) async throws {
     if !FileManager.default.createFile(atPath: diskURL.path, contents: nil) {
       throw OCIError.FailedToCreateVmFile
     }

Sources/tart/OCI/Layerizer/DiskV2.swift

@@ -7,6 +7,21 @@ class DiskV2: Disk {
   private static let bufferSizeBytes = 4 * 1024 * 1024
   private static let layerLimitBytes = 512 * 1024 * 1024
 
+  // A zero chunk for faster than byte-by-byte comparisons
+  //
+  // Assumes that the other Data(...) is equal in size, but it's fine to get a false-negative
+  // on the last block since it costs only 4 MiB of excess data per 512 MiB layer.
+  //
+  // Some simple benchmarks ("sync && sudo purge" command was used to negate the disk caching effects):
+  // +--------------------------------------+---------------------------------------------------+
+  // | Operation                            | time(1) result                                    |
+  // +--------------------------------------+---------------------------------------------------+
+  // | Data(...) == zeroChunk               | 2.16s user 11.71s system 73% cpu 18.928 total     |
+  // | Data(...).contains(where: {$0 != 0}) | 603.68s user 12.97s system 99% cpu 10:22.85 total |
+  // +--------------------------------------+---------------------------------------------------+
+  private static let holeGranularityBytes = 4 * 1024 * 1024
+  private static let zeroChunk = Data(count: holeGranularityBytes)
+
   static func push(diskURL: URL, registry: Registry, chunkSizeMb: Int, concurrency: UInt, progress: Progress) async throws -> [OCIManifestLayer] {
     var pushedLayers: [(index: Int, pushedLayer: OCIManifestLayer)] = []
 
@@ -69,12 +84,12 @@ class DiskV2: Disk {
     }
   }
 
-  static func pull(registry: Registry, diskLayers: [OCIManifestLayer], diskURL: URL, concurrency: UInt, progress: Progress, localLayerCache: LocalLayerCache? = nil) async throws {
+  static func pull(registry: Registry, diskLayers: [OCIManifestLayer], diskURL: URL, concurrency: UInt, progress: Progress, localLayerCache: LocalLayerCache? = nil, deduplicate: Bool = false) async throws {
     // Support resumable pulls
     let pullResumed = FileManager.default.fileExists(atPath: diskURL.path)
 
     if !pullResumed {
-      if let localLayerCache = localLayerCache {
+      if deduplicate, let localLayerCache = localLayerCache {
         // Clone the local layer cache's disk and use it as a base, potentially
         // reducing the space usage since some blocks won't be written at all
         try FileManager.default.copyItem(at: localLayerCache.diskURL, to: diskURL)
@@ -151,26 +166,31 @@ class DiskV2: Disk {
 
           // Also open the disk file for reading and verifying
           // its contents in case the local layer cache is used
-          let rdisk: FileHandle? = if localLayerCache != nil {
+          let rdisk: FileHandle? = if deduplicate && localLayerCache != nil {
             try FileHandle(forReadingFrom: diskURL)
           } else {
             nil
           }
 
-          // Check if we already have this layer contents in the local layer cache
-          if let localLayerCache = localLayerCache, let localLayerInfo = localLayerCache.findInfo(digest: diskLayer.digest, offsetHint: diskWritingOffset) {
-            // indicates that the locally cloned disk image has the same content at the given offset
-            let localHit = localLayerInfo.uncompressedContentDigest == uncompressedLayerContentDigest
-              && localLayerInfo.range.lowerBound == diskWritingOffset
-            // doesn't seem that localHit can ever be false if the localLayerCache is not nil
-            // but let's just add extra safety here and check it
-            if !localHit {
+          // Check if we already have this layer contents in the local layer cache,
+          // or perhaps even on the cloned disk (when the deduplication is enabled)
+          if let localLayerCache = localLayerCache,
+             let localLayerInfo = localLayerCache.findInfo(digest: diskLayer.digest, offsetHint: diskWritingOffset),
+             localLayerInfo.uncompressedContentDigest == uncompressedLayerContentDigest {
+            if deduplicate && localLayerInfo.range.lowerBound == diskWritingOffset {
+              // Do nothing, because the data is already on the disk that we've inherited from
+            } else {
               // Fulfil the layer contents from the local blob cache
               let data = localLayerCache.subdata(localLayerInfo.range)
               _ = try zeroSkippingWrite(disk, rdisk, fsBlockSize, diskWritingOffset, data)
             }
+
             try disk.close()
 
+            if let rdisk = rdisk {
+              try rdisk.close()
+            }
+
             // Update the progress
             progress.completedUnitCount += Int64(diskLayer.size)
 
@@ -198,6 +218,10 @@ class DiskV2: Disk {
           try filter.finalize()
 
           try disk.close()
+
+          if let rdisk = rdisk {
+            try rdisk.close()
+          }
         }
 
         globalDiskWritingOffset += uncompressedLayerSize
@@ -206,22 +230,6 @@ class DiskV2: Disk {
   }
 
   private static func zeroSkippingWrite(_ disk: FileHandle, _ rdisk: FileHandle?, _ fsBlockSize: UInt64, _ offset: UInt64, _ data: Data) throws -> UInt64 {
-    let holeGranularityBytes = 64 * 1024
-
-    // A zero chunk for faster than byte-by-byte comparisons
-    //
-    // Assumes that the other Data(...) is equal in size, but it's fine to get a false-negative
-    // on the last block since it costs only 64 KiB of excess data per 500 MB layer.
-    //
-    // Some simple benchmarks ("sync && sudo purge" command was used to negate the disk caching effects):
-    // +--------------------------------------+---------------------------------------------------+
-    // | Operation                            | time(1) result                                    |
-    // +--------------------------------------+---------------------------------------------------+
-    // | Data(...) == zeroChunk               | 2.16s user 11.71s system 73% cpu 18.928 total     |
-    // | Data(...).contains(where: {$0 != 0}) | 603.68s user 12.97s system 99% cpu 10:22.85 total |
-    // +--------------------------------------+---------------------------------------------------+
-    let zeroChunk = Data(count: holeGranularityBytes)
-
     var offset = offset
 
     for chunk in data.chunks(ofCount: holeGranularityBytes) {

Sources/tart/OCI/Reference/Generated/ReferenceBaseListener.swift

@@ -1,4 +1,4 @@
-// Generated from java-escape by ANTLR 4.11.1
+// Generated from Reference.g4 by ANTLR 4.13.2
 
 import Antlr4
 

Sources/tart/OCI/Reference/Generated/ReferenceLexer.swift

@@ -1,4 +1,4 @@
-// Generated from java-escape by ANTLR 4.11.1
+// Generated from Reference.g4 by ANTLR 4.13.2
 import Antlr4
 
 open class ReferenceLexer: Lexer {
@@ -49,7 +49,7 @@ open class ReferenceLexer: Lexer {
 
 	public
 	required init(_ input: CharStream) {
-	    RuntimeMetaData.checkVersion("4.11.1", RuntimeMetaData.VERSION)
+	    RuntimeMetaData.checkVersion("4.13.2", RuntimeMetaData.VERSION)
 		super.init(input)
 		_interp = LexerATNSimulator(self, ReferenceLexer._ATN, ReferenceLexer._decisionToDFA, ReferenceLexer._sharedContextCache)
 	}

Sources/tart/OCI/Reference/Generated/ReferenceListener.swift

@@ -1,4 +1,4 @@
-// Generated from java-escape by ANTLR 4.11.1
+// Generated from Reference.g4 by ANTLR 4.13.2
 import Antlr4
 
 /**

Sources/tart/OCI/Reference/Generated/ReferenceParser.swift

@@ -1,4 +1,4 @@
-// Generated from java-escape by ANTLR 4.11.1
+// Generated from Reference.g4 by ANTLR 4.13.2
 import Antlr4
 
 open class ReferenceParser: Parser {
@@ -41,7 +41,7 @@ open class ReferenceParser: Parser {
 	static let VOCABULARY = Vocabulary(_LITERAL_NAMES, _SYMBOLIC_NAMES)
 
 	override open
-	func getGrammarFileName() -> String { return "java-escape" }
+	func getGrammarFileName() -> String { return "Reference.g4" }
 
 	override open
 	func getRuleNames() -> [String] { return ReferenceParser.ruleNames }
@@ -60,7 +60,7 @@ open class ReferenceParser: Parser {
 
 	override public
 	init(_ input:TokenStream) throws {
-	    RuntimeMetaData.checkVersion("4.11.1", RuntimeMetaData.VERSION)
+	    RuntimeMetaData.checkVersion("4.13.2", RuntimeMetaData.VERSION)
 		try super.init(input)
 		_interp = ParserATNSimulator(self,ReferenceParser._ATN,ReferenceParser._decisionToDFA, ReferenceParser._sharedContextCache)
 	}
@@ -460,7 +460,7 @@ open class ReferenceParser: Parser {
 		 		setState(63)
 		 		try _errHandler.sync(self)
 		 		_la = try _input.LA(1)
-		 		if ((Int64(_la) & ~0x3f) == 0 && ((Int64(1) << _la) & 88) != 0) {
+		 		if (((Int64(_la) & ~0x3f) == 0 && ((Int64(1) << _la) & 88) != 0)) {
 		 			setState(62)
 		 			try separator()
 
@@ -611,7 +611,7 @@ open class ReferenceParser: Parser {
 		 	setState(84)
 		 	try _errHandler.sync(self)
 		 	_la = try _input.LA(1)
-		 	while ((Int64(_la) & ~0x3f) == 0 && ((Int64(1) << _la) & 88) != 0) {
+		 	while (((Int64(_la) & ~0x3f) == 0 && ((Int64(1) << _la) & 88) != 0)) {
 		 		setState(79)
 		 		try separator()
 		 		setState(80)
@@ -664,7 +664,7 @@ open class ReferenceParser: Parser {
 		 	try enterOuterAlt(_localctx, 1)
 		 	setState(87)
 		 	_la = try _input.LA(1)
-		 	if (!((Int64(_la) & ~0x3f) == 0 && ((Int64(1) << _la) & 88) != 0)) {
+		 	if (!(((Int64(_la) & ~0x3f) == 0 && ((Int64(1) << _la) & 88) != 0))) {
 		 	try _errHandler.recoverInline(self)
 		 	}
 		 	else {

Sources/tart/OCI/Registry.swift

@@ -1,6 +1,5 @@
 import Foundation
 import Algorithms
-import AsyncAlgorithms
 
 enum RegistryError: Error {
   case UnexpectedHTTPStatusCode(when: String, code: Int, details: String = "")
@@ -31,7 +30,7 @@ extension Data {
   }
 }
 
-extension AsyncThrowingChannel<Data, Error> {
+extension AsyncThrowingStream<Data, Error> {
   func asData() async throws -> Data {
     var result = Data()
 
@@ -307,7 +306,7 @@ class Registry {
     body: Data? = nil,
     doAuth: Bool = true,
     viaFile: Bool = false
-  ) async throws -> (AsyncThrowingChannel<Data, Error>, HTTPURLResponse) {
+  ) async throws -> (AsyncThrowingStream<Data, Error>, HTTPURLResponse) {
     var urlComponents = urlComponents
 
     if urlComponents.queryItems == nil && !parameters.isEmpty {
@@ -327,12 +326,12 @@ class Registry {
       request.httpBody = body
     }
 
-    var (channel, response) = try await authAwareRequest(request: request, viaFile: viaFile)
+    var (channel, response) = try await authAwareRequest(request: request, viaFile: viaFile, doAuth: doAuth)
 
     if doAuth && response.statusCode == HTTPCode.Unauthorized.rawValue {
       _ = try await channel.asData()
       try await auth(response: response)
-      (channel, response) = try await authAwareRequest(request: request, viaFile: viaFile)
+      (channel, response) = try await authAwareRequest(request: request, viaFile: viaFile, doAuth: doAuth)
     }
 
     return (channel, response)
@@ -413,11 +412,13 @@ class Registry {
     return nil
   }
 
-  private func authAwareRequest(request: URLRequest, viaFile: Bool = false) async throws -> (AsyncThrowingChannel<Data, Error>, HTTPURLResponse) {
+  private func authAwareRequest(request: URLRequest, viaFile: Bool = false, doAuth: Bool) async throws -> (AsyncThrowingStream<Data, Error>, HTTPURLResponse) {
     var request = request
 
-    if let (name, value) = await authenticationKeeper.header() {
-      request.addValue(value, forHTTPHeaderField: name)
+    if doAuth {
+      if let (name, value) = await authenticationKeeper.header() {
+        request.addValue(value, forHTTPHeaderField: name)
+      }
     }
 
     request.setValue("Tart/\(CI.version) (\(DeviceInfo.os); \(DeviceInfo.model))",

Sources/tart/PIDLock.swift

@@ -11,7 +11,7 @@ class PIDLock {
     if fd == -1 {
       let details = Errno(rawValue: CInt(errno))
 
-      throw RuntimeError.PIDLockFailed("failed to open lock file \(url): \(details)")
+      throw RuntimeError.PIDLockMissing("failed to open lock file \(url): \(details)")
     }
   }
 

Sources/tart/Platform/Darwin.swift

@@ -38,7 +38,7 @@ struct UnsupportedHostOSError: Error, CustomStringConvertible {
         throw DecodingError.dataCorruptedError(forKey: .hardwareModel, in: container, debugDescription: "")
       }
       guard let hardwareModel = VZMacHardwareModel.init(dataRepresentation: data) else {
-        throw DecodingError.dataCorruptedError(forKey: .hardwareModel, in: container, debugDescription: "")
+        throw UnsupportedHostOSError()
       }
       self.hardwareModel = hardwareModel
     }
@@ -58,7 +58,11 @@ struct UnsupportedHostOSError: Error, CustomStringConvertible {
       VZMacOSBootLoader()
     }
 
-    func platform(nvramURL: URL) throws -> VZPlatformConfiguration {
+    func platform(nvramURL: URL, needsNestedVirtualization: Bool) throws -> VZPlatformConfiguration {
+      if needsNestedVirtualization {
+        throw RuntimeError.VMConfigurationError("macOS virtual machines do not support nested virtualization")
+      }
+
       let result = VZMacPlatformConfiguration()
 
       result.machineIdentifier = ecid

Sources/tart/Platform/Linux.swift

@@ -14,8 +14,12 @@ struct Linux: Platform {
     return result
   }
 
-  func platform(nvramURL: URL) throws -> VZPlatformConfiguration {
-    VZGenericPlatformConfiguration()
+  func platform(nvramURL: URL, needsNestedVirtualization: Bool) throws -> VZPlatformConfiguration {
+    let config = VZGenericPlatformConfiguration()
+    if #available(macOS 15, *) {
+      config.isNestedVirtualizationEnabled = needsNestedVirtualization
+    }
+    return config
   }
 
   func graphicsDevice(vmConfig: VMConfig) -> VZGraphicsDeviceConfiguration {

Sources/tart/Platform/Platform.swift

@@ -3,7 +3,7 @@ import Virtualization
 protocol Platform: Codable {
   func os() -> OS
   func bootLoader(nvramURL: URL) throws -> VZBootLoader
-  func platform(nvramURL: URL) throws -> VZPlatformConfiguration
+  func platform(nvramURL: URL, needsNestedVirtualization: Bool) throws -> VZPlatformConfiguration
   func graphicsDevice(vmConfig: VMConfig) -> VZGraphicsDeviceConfiguration
   func keyboards() -> [VZKeyboardConfiguration]
   func pointingDevices() -> [VZPointingDeviceConfiguration]

Sources/tart/URL+AccessDate.swift

@@ -1,4 +1,5 @@
 import Foundation
+import System
 
 extension URL {
   func accessDate() throws -> Date {
@@ -13,7 +14,9 @@ extension URL {
     let times = [accessDate.asTimeval(), modificationDate.asTimeval()]
     let ret = utimes(path, times)
     if ret != 0 {
-      throw RuntimeError.FailedToUpdateAccessDate("utimes(2) failed: \(ret.explanation())")
+      let details = Errno(rawValue: CInt(errno))
+
+      throw RuntimeError.FailedToUpdateAccessDate("utimes(2) failed: \(details)")
     }
   }
 }

Sources/tart/VM.swift

@@ -1,6 +1,5 @@
 import Foundation
 import Virtualization
-import AsyncAlgorithms
 import Semaphore
 
 struct UnsupportedRestoreImageError: Error {
@@ -47,9 +46,11 @@ class VM: NSObject, VZVirtualMachineDelegate, ObservableObject {
        directorySharingDevices: [VZDirectorySharingDeviceConfiguration] = [],
        serialPorts: [VZSerialPortConfiguration] = [],
        suspendable: Bool = false,
+       nested: Bool = false,
        audio: Bool = true,
        clipboard: Bool = true,
-       sync: VZDiskImageSynchronizationMode = .full
+       sync: VZDiskImageSynchronizationMode = .full,
+       caching: VZDiskImageCachingMode? = nil
   ) throws {
     name = vmDir.name
     config = try VMConfig.init(fromURL: vmDir.configURL)
@@ -66,9 +67,11 @@ class VM: NSObject, VZVirtualMachineDelegate, ObservableObject {
                                                 directorySharingDevices: directorySharingDevices,
                                                 serialPorts: serialPorts,
                                                 suspendable: suspendable,
+                                                nested: nested,
                                                 audio: audio,
                                                 clipboard: clipboard,
-                                                sync: sync
+                                                sync: sync,
+                                                caching: caching
     )
     virtualMachine = VZVirtualMachine(configuration: configuration)
 
@@ -295,9 +298,11 @@ class VM: NSObject, VZVirtualMachineDelegate, ObservableObject {
     directorySharingDevices: [VZDirectorySharingDeviceConfiguration],
     serialPorts: [VZSerialPortConfiguration],
     suspendable: Bool = false,
+    nested: Bool = false,
     audio: Bool = true,
     clipboard: Bool = true,
-    sync: VZDiskImageSynchronizationMode = .full
+    sync: VZDiskImageSynchronizationMode = .full,
+    caching: VZDiskImageCachingMode? = nil
   ) throws -> VZVirtualMachineConfiguration {
     let configuration = VZVirtualMachineConfiguration()
 
@@ -309,7 +314,7 @@ class VM: NSObject, VZVirtualMachineDelegate, ObservableObject {
     configuration.memorySize = vmConfig.memorySize
 
     // Platform
-    configuration.platform = try vmConfig.platform.platform(nvramURL: nvramURL)
+    configuration.platform = try vmConfig.platform.platform(nvramURL: nvramURL, needsNestedVirtualization: nested)
 
     // Display
     configuration.graphicsDevices = [vmConfig.platform.graphicsDevice(vmConfig: vmConfig)]
@@ -317,15 +322,19 @@ class VM: NSObject, VZVirtualMachineDelegate, ObservableObject {
     // Audio
     let soundDeviceConfiguration = VZVirtioSoundDeviceConfiguration()
 
-    let inputAudioStreamConfiguration = VZVirtioSoundDeviceInputStreamConfiguration()
-    let outputAudioStreamConfiguration = VZVirtioSoundDeviceOutputStreamConfiguration()
-
     if audio && !suspendable {
+      let inputAudioStreamConfiguration = VZVirtioSoundDeviceInputStreamConfiguration()
+      let outputAudioStreamConfiguration = VZVirtioSoundDeviceOutputStreamConfiguration()
+
       inputAudioStreamConfiguration.source = VZHostAudioInputStreamSource()
       outputAudioStreamConfiguration.sink = VZHostAudioOutputStreamSink()
+
+      soundDeviceConfiguration.streams = [inputAudioStreamConfiguration, outputAudioStreamConfiguration]
+    } else {
+      // just a null speaker
+      soundDeviceConfiguration.streams = [VZVirtioSoundDeviceOutputStreamConfiguration()]
     }
 
-    soundDeviceConfiguration.streams = [inputAudioStreamConfiguration, outputAudioStreamConfiguration]
     configuration.audioDevices = [soundDeviceConfiguration]
 
     // Keyboard and mouse
@@ -356,18 +365,17 @@ class VM: NSObject, VZVirtualMachineDelegate, ObservableObject {
     }
 
     // Storage
-    let attachment: VZDiskImageStorageDeviceAttachment = vmConfig.os == .linux ?
-      // Use "cached" caching mode for virtio drive to prevent fs corruption on linux
-      try VZDiskImageStorageDeviceAttachment(url: diskURL, readOnly: false, cachingMode: .cached, synchronizationMode: sync) :
-      try VZDiskImageStorageDeviceAttachment(url: diskURL, readOnly: false, cachingMode: .automatic, synchronizationMode: sync)
+    let attachment: VZDiskImageStorageDeviceAttachment =  try VZDiskImageStorageDeviceAttachment(
+      url: diskURL,
+      readOnly: false,
+      // When not specified, use "cached" caching mode for Linux VMs to prevent file-system corruption[1]
+      //
+      // [1]: https://github.com/cirruslabs/tart/pull/675
+      cachingMode: caching ?? (vmConfig.os == .linux ? .cached : .automatic),
+      synchronizationMode: sync
+    )
 
-    var device: VZStorageDeviceConfiguration
-    if #available(macOS 14, *), vmConfig.os == .linux {
-      device = VZNVMExpressControllerDeviceConfiguration(attachment: attachment)
-    } else {
-      device = VZVirtioBlockDeviceConfiguration(attachment: attachment)
-    }
-    var devices: [VZStorageDeviceConfiguration] = [device]
+    var devices: [VZStorageDeviceConfiguration] = [VZVirtioBlockDeviceConfiguration(attachment: attachment)]
     devices.append(contentsOf: additionalStorageDevices)
     configuration.storageDevices = devices
 

Sources/tart/VMConfig.swift

@@ -24,6 +24,7 @@ enum CodingKeys: String, CodingKey {
   case memorySize
   case macAddress
   case display
+  case displayRefit
 
   // macOS-specific keys
   case ecid
@@ -52,6 +53,7 @@ struct VMConfig: Codable {
   private(set) var memorySize: UInt64
   var macAddress: VZMACAddress
   var display: VMDisplayConfig = VMDisplayConfig()
+  var displayRefit: Bool?
 
   init(
     platform: Platform,
@@ -121,6 +123,7 @@ struct VMConfig: Codable {
     self.macAddress = macAddress
 
     display = try container.decodeIfPresent(VMDisplayConfig.self, forKey: .display) ?? VMDisplayConfig()
+    displayRefit = try container.decodeIfPresent(Bool.self, forKey: .displayRefit)
   }
 
   func encode(to encoder: Encoder) throws {
@@ -136,6 +139,9 @@ struct VMConfig: Codable {
     try container.encode(memorySize, forKey: .memorySize)
     try container.encode(macAddress.string, forKey: .macAddress)
     try container.encode(display, forKey: .display)
+    if let displayRefit = displayRefit {
+      try container.encode(displayRefit, forKey: .displayRefit)
+    }
   }
 
   mutating func setCPU(cpuCount: Int) throws {

Sources/tart/VMDirectory+OCI.swift

@@ -11,7 +11,7 @@ enum OCIError: Error {
 }
 
 extension VMDirectory {
-  func pullFromRegistry(registry: Registry, manifest: OCIManifest, concurrency: UInt, localLayerCache: LocalLayerCache?) async throws {
+  func pullFromRegistry(registry: Registry, manifest: OCIManifest, concurrency: UInt, localLayerCache: LocalLayerCache?, deduplicate: Bool) async throws {
     // Pull VM's config file layer and re-serialize it into a config file
     let configLayers = manifest.layers.filter {
       $0.mediaType == configMediaType
@@ -54,12 +54,13 @@ extension VMDirectory {
     do {
       try await diskImplType.pull(registry: registry, diskLayers: layers, diskURL: diskURL,
                                   concurrency: concurrency, progress: progress,
-                                  localLayerCache: localLayerCache)
+                                  localLayerCache: localLayerCache,
+                                  deduplicate: deduplicate)
     } catch let error where error is FilterError {
       throw RuntimeError.PullFailed("failed to decompress disk: \(error.localizedDescription)")
     }
 
-    if let llc = localLayerCache {
+    if deduplicate, let llc = localLayerCache {
       // set custom attribute to remember deduplicated bytes
       diskURL.setDeduplicatedBytes(llc.deduplicatedBytes)
     }

Sources/tart/VMStorageHelper.swift

@@ -24,6 +24,8 @@ class VMStorageHelper {
   private static func missingVMWrap<R: Any>(_ name: String, closure: () throws -> R) throws -> R {
     do {
       return try closure()
+    } catch RuntimeError.PIDLockMissing {
+      throw RuntimeError.VMDoesNotExist(name: name)
     } catch {
       if error.isFileNotFound() {
         throw RuntimeError.VMDoesNotExist(name: name)
@@ -59,6 +61,7 @@ enum RuntimeError : Error {
   case InvalidDiskSize(_ message: String)
   case FailedToUpdateAccessDate(_ message: String)
   case PIDLockFailed(_ message: String)
+  case PIDLockMissing(_ message: String)
   case FailedToParseRemoteName(_ message: String)
   case VMTerminationFailed(_ message: String)
   case ImproperlyFormattedHost(_ host: String, _ hint: String)
@@ -71,6 +74,7 @@ enum RuntimeError : Error {
   case OCIUnsupportedDiskFormat(_ format: String)
   case SuspendFailed(_ message: String)
   case PullFailed(_ message: String)
+  case VirtualMachineLimitExceeded(_ hint: String)
 }
 
 protocol HasExitCode {
@@ -104,6 +108,8 @@ extension RuntimeError : CustomStringConvertible {
       return message
     case .PIDLockFailed(let message):
       return message
+    case .PIDLockMissing(let message):
+      return message
     case .FailedToParseRemoteName(let cause):
       return "failed to parse remote name: \(cause)"
     case .VMTerminationFailed(let message):
@@ -128,6 +134,8 @@ extension RuntimeError : CustomStringConvertible {
       return "Failed to suspend the VM: \(message)"
     case .PullFailed(let message):
       return message
+    case .VirtualMachineLimitExceeded(let hint):
+      return "The number of VMs exceeds the system limit\(hint)"
     }
   }
 }

Sources/tart/VMStorageOCI.swift

@@ -140,7 +140,7 @@ class VMStorageOCI: PrunableStorage {
     try list().filter { (_, _, isSymlink) in !isSymlink }.map { (_, vmDir, _) in vmDir }
   }
 
-  func pull(_ name: RemoteName, registry: Registry, concurrency: UInt) async throws {
+  func pull(_ name: RemoteName, registry: Registry, concurrency: UInt, deduplicate: Bool) async throws {
     SentrySDK.configureScope { scope in
       scope.setContext(value: ["imageName": name.description], key: "OCI")
     }
@@ -203,12 +203,16 @@ class VMStorageOCI: PrunableStorage {
           if let llc = localLayerCache {
             let deduplicatedHuman = ByteCountFormatter.string(fromByteCount: Int64(llc.deduplicatedBytes), countStyle: .file)
 
-            defaultLogger.appendNewLine("found an image \(llc.name) that will allow us to deduplicate \(deduplicatedHuman), using it as a base...")
+            if deduplicate {
+              defaultLogger.appendNewLine("found an image \(llc.name) that will allow us to deduplicate \(deduplicatedHuman), using it as a base...")
+            } else {
+              defaultLogger.appendNewLine("found an image \(llc.name) that will allow us to avoid fetching \(deduplicatedHuman), will try use it...")
+            }
           }
 
-          try await tmpVMDir.pullFromRegistry(registry: registry, manifest: manifest, concurrency: concurrency, localLayerCache: localLayerCache)
+          try await tmpVMDir.pullFromRegistry(registry: registry, manifest: manifest, concurrency: concurrency, localLayerCache: localLayerCache, deduplicate: deduplicate)
         } recoverFromFailure: { error in
-          if error is Retryable {
+          if error is URLError {
             print("Error: \(error.localizedDescription)")
             print("Attempting to re-try...")
 
@@ -235,6 +239,9 @@ class VMStorageOCI: PrunableStorage {
       // are excluded from garbage collection
       VMDirectory(baseURL: vmURL(name)).markExplicitlyPulled()
     }
+
+    // to explicitly set the image as being accessed so it won't get pruned immediately
+    _ = try VMStorageOCI().open(name)
   }
 
   func linked(from: RemoteName, to: RemoteName) -> Bool {

Tests/TartTests/Util/RegistryRunner.swift

@@ -31,7 +31,7 @@ class RegistryRunner {
 
   init() async throws {
     // Start container
-    let container = try Self.dockerCmd("run", "-d", "--rm", "-p", "5000", "registry:2")
+    let container = try Self.dockerCmd("run", "-d", "--rm", "-p", "127.0.0.1:0:5000", "registry:2")
       .trimmingCharacters(in: CharacterSet.newlines)
     containerID = container
 

benchmark/README.md

@@ -2,10 +2,18 @@
 
 Tart comes with a Golang-based benchmarking utility that allows one to easily compare host and guest performance.
 
-Currently, only Flexible I/O tester workloads are supported. To run them, [install Golang](https://go.dev/) and run the following command from this (`benchmark/`) directory:
+Currently, only Flexible I/O tester workloads are supported. To run them, first make sure that [passwordless sudo](https://serverfault.com/questions/160581/how-to-setup-passwordless-sudo-on-linux) is configured.
+
+Then, [install Golang](https://go.dev/). The easiest way is through [Homebrew](https://brew.sh/):
 
 ```shell
-go run cmd/main.go fio
+brew install go
+```
+
+Finally, run the following command from this (`benchmark/`) directory:
+
+```shell
+go run cmd/main.go fio --image ghcr.io/cirruslabs/macos-sonoma-base:latest --prepare 'sudo purge && sync'
 ```
 
 You can also enable the debugging output to diagnose issues:
@@ -16,6 +24,8 @@ go run cmd/main.go fio --debug
 
 ## Results
 
+### Mar 27, 2024
+
 Host:
 
 * Hardware: Mac mini (Apple M2 Pro, 8 performance and 4 efficiency cores, 32 GB RAM, `Mac14,12`)
@@ -37,3 +47,141 @@ Random writing of 100MB 	Tart    	2.0 GB/s 	493.31 kIOPS
 Random writing of 1000MB	local   	1.7 GB/s 	414.89 kIOPS  
 Random writing of 1000MB	Tart    	1.1 GB/s 	287.4 kIOPS  
 ```
+
+### Dec 2, 2024
+
+Host:
+
+* Hardware: MacBook Pro (Apple M1 Pro, 8 performance and 2 efficiency cores, 32 GB RAM, `MacBookPro18,3`)
+* OS: macOS Sequoia 15.1.1
+
+Guest:
+
+* Hardware: [Virtualization.Framework](https://developer.apple.com/documentation/virtualization)
+* OS: macOS Sonoma 14.6
+
+```
+Name                                    	Executor                                          	B/W (read)	B/W (write)	I/O (read) 	I/O (write) 	Latency (read)          	Latency (write)         	Latency (sync)      
+Single 4KiB random write process        	local                                             	0 B/s     	19 MB/s    	0 IOPS     	4.81 kIOPS  	0s ± 0s                 	203.418µs ± 155.865µs   	0s ± 0s             
+Single 4KiB random write process        	Tart                                              	0 B/s     	18 MB/s    	0 IOPS     	4.54 kIOPS  	0s ± 0s                 	213.655µs ± 188.822µs   	0s ± 0s             
+Single 4KiB random write process        	Tart (--root-disk-opts="sync=none")               	0 B/s     	19 MB/s    	0 IOPS     	4.68 kIOPS  	0s ± 0s                 	208.413µs ± 183.45µs    	0s ± 0s             
+Single 4KiB random write process        	Tart (--root-disk-opts="caching=cached")          	0 B/s     	24 MB/s    	0 IOPS     	6.11 kIOPS  	0s ± 0s                 	158.07µs ± 2.294654ms   	0s ± 0s             
+Single 4KiB random write process        	Tart (--root-disk-opts="sync=none,caching=cached")	0 B/s     	22 MB/s    	0 IOPS     	5.49 kIOPS  	0s ± 0s                 	173.414µs ± 310.213µs   	0s ± 0s             
+16 parallel 64KiB random write processes	local                                             	0 B/s     	18 GB/s    	0 IOPS     	273.76 kIOPS	0s ± 0s                 	323.423µs ± 604.999µs   	0s ± 0s             
+16 parallel 64KiB random write processes	Tart                                              	0 B/s     	16 GB/s    	0 IOPS     	273.48 kIOPS	0s ± 0s                 	335.086µs ± 7.591748ms  	0s ± 0s             
+16 parallel 64KiB random write processes	Tart (--root-disk-opts="sync=none")               	0 B/s     	18 GB/s    	0 IOPS     	281.49 kIOPS	0s ± 0s                 	326.655µs ± 7.485473ms  	0s ± 0s             
+16 parallel 64KiB random write processes	Tart (--root-disk-opts="caching=cached")          	0 B/s     	17 GB/s    	0 IOPS     	266.79 kIOPS	0s ± 0s                 	340µs ± 7.868384ms      	0s ± 0s             
+16 parallel 64KiB random write processes	Tart (--root-disk-opts="sync=none,caching=cached")	0 B/s     	16 GB/s    	0 IOPS     	251.02 kIOPS	0s ± 0s                 	355.077µs ± 8.354218ms  	0s ± 0s             
+Single 1MiB random write process        	local                                             	0 B/s     	1.3 GB/s   	0 IOPS     	1.31 kIOPS  	0s ± 0s                 	751.716µs ± 370.731µs   	0s ± 0s             
+Single 1MiB random write process        	Tart                                              	0 B/s     	1.1 GB/s   	0 IOPS     	1.1 kIOPS   	0s ± 0s                 	885.833µs ± 3.572539ms  	0s ± 0s             
+Single 1MiB random write process        	Tart (--root-disk-opts="sync=none")               	0 B/s     	1.1 GB/s   	0 IOPS     	1.08 kIOPS  	0s ± 0s                 	898.427µs ± 3.464261ms  	0s ± 0s             
+Single 1MiB random write process        	Tart (--root-disk-opts="caching=cached")          	0 B/s     	1000 MB/s  	0 IOPS     	976.47 IOPS 	0s ± 0s                 	972.491µs ± 6.87654ms   	0s ± 0s             
+Single 1MiB random write process        	Tart (--root-disk-opts="sync=none,caching=cached")	0 B/s     	1.1 GB/s   	0 IOPS     	1.03 kIOPS  	0s ± 0s                 	925.545µs ± 4.261693ms  	0s ± 0s             
+Random reads/writes (4k)                	local                                             	62 MB/s   	62 MB/s    	15.37 kIOPS	15.37 kIOPS 	2.059453ms ± 1.431822ms 	2.098761ms ± 1.445082ms 	0s ± 0s             
+Random reads/writes (4k)                	Tart                                              	38 MB/s   	38 MB/s    	9.6 kIOPS  	9.61 kIOPS  	3.30369ms ± 1.500464ms  	3.350589ms ± 1.512986ms 	0s ± 0s             
+Random reads/writes (4k)                	Tart (--root-disk-opts="sync=none")               	39 MB/s   	39 MB/s    	9.82 kIOPS 	9.83 kIOPS  	3.228106ms ± 1.367512ms 	3.27626ms ± 1.385964ms  	0s ± 0s             
+Random reads/writes (4k)                	Tart (--root-disk-opts="caching=cached")          	35 MB/s   	35 MB/s    	8.74 kIOPS 	8.76 kIOPS  	3.640772ms ± 15.472355ms	3.661779ms ± 15.264288ms	0s ± 0s             
+Random reads/writes (4k)                	Tart (--root-disk-opts="sync=none,caching=cached")	24 MB/s   	24 MB/s    	5.98 kIOPS 	5.99 kIOPS  	5.31188ms ± 4.55205ms   	5.375047ms ± 5.113847ms 	0s ± 0s             
+Random reads/writes (64k)               	local                                             	435 MB/s  	436 MB/s   	6.79 kIOPS 	6.8 kIOPS   	4.955892ms ± 2.066685ms 	4.440414ms ± 1.860036ms 	0s ± 0s             
+Random reads/writes (64k)               	Tart                                              	352 MB/s  	353 MB/s   	5.5 kIOPS  	5.51 kIOPS  	5.946067ms ± 2.041124ms 	5.658948ms ± 1.928372ms 	0s ± 0s             
+Random reads/writes (64k)               	Tart (--root-disk-opts="sync=none")               	331 MB/s  	332 MB/s   	5.16 kIOPS 	5.17 kIOPS  	6.330765ms ± 1.726782ms 	6.033862ms ± 1.671028ms 	0s ± 0s             
+Random reads/writes (64k)               	Tart (--root-disk-opts="caching=cached")          	428 MB/s  	428 MB/s   	6.68 kIOPS 	6.69 kIOPS  	4.661666ms ± 18.342779ms	4.904961ms ± 18.396772ms	0s ± 0s             
+Random reads/writes (64k)               	Tart (--root-disk-opts="sync=none,caching=cached")	297 MB/s  	298 MB/s   	4.64 kIOPS 	4.65 kIOPS  	6.591009ms ± 2.827053ms 	7.166883ms ± 3.001036ms 	0s ± 0s             
+sync test                               	local                                             	0 B/s     	48 MB/s    	0 IOPS     	21.15 kIOPS 	0s ± 0s                 	23.471µs ± 81.868µs     	23.374µs ± 6.255µs  
+sync test                               	Tart                                              	0 B/s     	24 MB/s    	0 IOPS     	10.72 kIOPS 	0s ± 0s                 	24.983µs ± 61.761µs     	67.575µs ± 76.196µs 
+sync test                               	Tart (--root-disk-opts="sync=none")               	0 B/s     	21 MB/s    	0 IOPS     	9.5 kIOPS   	0s ± 0s                 	26.973µs ± 63.935µs     	77.388µs ± 47.103µs 
+sync test                               	Tart (--root-disk-opts="caching=cached")          	0 B/s     	30 MB/s    	0 IOPS     	13.19 kIOPS 	0s ± 0s                 	11.923µs ± 25.225µs     	62.894µs ± 208.933µs
+sync test                               	Tart (--root-disk-opts="sync=none,caching=cached")	0 B/s     	38 MB/s    	0 IOPS     	17.02 kIOPS 	0s ± 0s                 	10.124µs ± 21.868µs     	47.803µs ± 33.706µs
+```
+
+### Dec 4, 2024
+
+Host:
+
+* AWS instance: `mac2.metal` + `gp3` EBS volume
+* Hardware: Mac mini (Apple M1, 4 performance and 4 efficiency cores, 16 GB RAM, `Macmini9,1`)
+* OS: macOS Sequoia 15.0
+
+Guest:
+
+* Hardware: [Virtualization.Framework](https://developer.apple.com/documentation/virtualization)
+* OS: macOS Sonoma 14.6
+
+```
+Name                                    	Executor                                          	B/W (read)	B/W (write)	I/O (read) 	I/O (write) 	Latency (read)            	Latency (write)           	Latency (sync)         
+Single 4KiB random write process        	local                                             	0 B/s     	4.4 MB/s   	0 IOPS     	1.1 kIOPS   	0s ± 0s                   	702.357µs ± 359.925µs     	0s ± 0s                
+Single 4KiB random write process        	Tart                                              	0 B/s     	2.6 MB/s   	0 IOPS     	656.37 IOPS 	0s ± 0s                   	1.140086ms ± 1.450472ms   	0s ± 0s                
+Single 4KiB random write process        	Tart (--root-disk-opts="sync=none")               	0 B/s     	2.7 MB/s   	0 IOPS     	677.07 IOPS 	0s ± 0s                   	1.179872ms ± 1.219626ms   	0s ± 0s                
+Single 4KiB random write process        	Tart (--root-disk-opts="caching=cached")          	0 B/s     	3.3 MB/s   	0 IOPS     	832.66 IOPS 	0s ± 0s                   	948.648µs ± 94.141338ms   	0s ± 0s                
+Single 4KiB random write process        	Tart (--root-disk-opts="sync=none,caching=cached")	0 B/s     	15 MB/s    	0 IOPS     	3.65 kIOPS  	0s ± 0s                   	260.717µs ± 19.977757ms   	0s ± 0s                
+16 parallel 64KiB random write processes	local                                             	0 B/s     	9.5 GB/s   	0 IOPS     	147.89 kIOPS	0s ± 0s                   	753.289µs ± 8.028974ms    	0s ± 0s                
+16 parallel 64KiB random write processes	Tart                                              	0 B/s     	10 GB/s    	0 IOPS     	176.96 kIOPS	0s ± 0s                   	429.83µs ± 33.792264ms    	0s ± 0s                
+16 parallel 64KiB random write processes	Tart (--root-disk-opts="sync=none")               	0 B/s     	12 GB/s    	0 IOPS     	180.89 kIOPS	0s ± 0s                   	383.524µs ± 17.524971ms   	0s ± 0s                
+16 parallel 64KiB random write processes	Tart (--root-disk-opts="caching=cached")          	0 B/s     	336 MB/s   	0 IOPS     	5.24 kIOPS  	0s ± 0s                   	9.970844ms ± 365.808663ms 	0s ± 0s                
+16 parallel 64KiB random write processes	Tart (--root-disk-opts="sync=none,caching=cached")	0 B/s     	9.4 GB/s   	0 IOPS     	147.04 kIOPS	0s ± 0s                   	524.139µs ± 34.100009ms   	0s ± 0s                
+Single 1MiB random write process        	local                                             	0 B/s     	178 MB/s   	0 IOPS     	173.36 IOPS 	0s ± 0s                   	3.835103ms ± 2.917977ms   	0s ± 0s                
+Single 1MiB random write process        	Tart                                              	0 B/s     	140 MB/s   	0 IOPS     	136.48 IOPS 	0s ± 0s                   	4.721178ms ± 7.744965ms   	0s ± 0s                
+Single 1MiB random write process        	Tart (--root-disk-opts="sync=none")               	0 B/s     	144 MB/s   	0 IOPS     	140.63 IOPS 	0s ± 0s                   	4.443507ms ± 11.572454ms  	0s ± 0s                
+Single 1MiB random write process        	Tart (--root-disk-opts="caching=cached")          	0 B/s     	47 MB/s    	0 IOPS     	45.55 IOPS  	0s ± 0s                   	13.267881ms ± 358.283094ms	0s ± 0s                
+Single 1MiB random write process        	Tart (--root-disk-opts="sync=none,caching=cached")	0 B/s     	196 MB/s   	0 IOPS     	191.4 IOPS  	0s ± 0s                   	4.102516ms ± 73.117503ms  	0s ± 0s                
+Random reads/writes (4k)                	local                                             	8.7 MB/s  	8.7 MB/s   	2.16 kIOPS 	2.16 kIOPS  	193.370794ms ± 42.593607ms	222.272016ms ± 56.586971ms	0s ± 0s                
+Random reads/writes (4k)                	Tart                                              	4.1 MB/s  	4.1 MB/s   	1.02 kIOPS 	1.03 kIOPS  	31.038867ms ± 13.508668ms 	31.184305ms ± 14.032766ms 	0s ± 0s                
+Random reads/writes (4k)                	Tart (--root-disk-opts="sync=none")               	4.2 MB/s  	4.2 MB/s   	1.04 kIOPS 	1.05 kIOPS  	30.368422ms ± 13.505627ms 	30.595412ms ± 13.840944ms 	0s ± 0s                
+Random reads/writes (4k)                	Tart (--root-disk-opts="caching=cached")          	2.2 MB/s  	2.2 MB/s   	545.33 IOPS	548.86 IOPS 	59.31316ms ± 716.351086ms 	57.647852ms ± 711.503882ms	0s ± 0s                
+Random reads/writes (4k)                	Tart (--root-disk-opts="sync=none,caching=cached")	6.0 MB/s  	6.0 MB/s   	1.5 kIOPS  	1.5 kIOPS   	21.244222ms ± 47.808399ms 	21.39459ms ± 44.716307ms  	0s ± 0s                
+Random reads/writes (64k)               	local                                             	121 MB/s  	121 MB/s   	1.89 kIOPS 	1.89 kIOPS  	61.894699ms ± 21.353345ms 	73.176462ms ± 13.02948ms  	0s ± 0s                
+Random reads/writes (64k)               	Tart                                              	72 MB/s   	72 MB/s    	1.12 kIOPS 	1.12 kIOPS  	27.842263ms ± 15.320781ms 	29.161858ms ± 15.765314ms 	0s ± 0s                
+Random reads/writes (64k)               	Tart (--root-disk-opts="sync=none")               	71 MB/s   	72 MB/s    	1.11 kIOPS 	1.11 kIOPS  	28.009493ms ± 16.333136ms 	29.285868ms ± 16.540589ms 	0s ± 0s                
+Random reads/writes (64k)               	Tart (--root-disk-opts="caching=cached")          	28 MB/s   	28 MB/s    	441.85 IOPS	444.81 IOPS 	71.726725ms ± 633.215756ms	72.597238ms ± 630.969305ms	0s ± 0s                
+Random reads/writes (64k)               	Tart (--root-disk-opts="sync=none,caching=cached")	81 MB/s   	81 MB/s    	1.26 kIOPS 	1.26 kIOPS  	24.872043ms ± 36.980111ms 	25.568559ms ± 37.027145ms 	0s ± 0s                
+sync test                               	local                                             	0 B/s     	1.9 MB/s   	0 IOPS     	868.08 IOPS 	0s ± 0s                   	92.08µs ± 233.598µs       	1.059033ms ± 98.751µs  
+sync test                               	Tart                                              	0 B/s     	1.5 MB/s   	0 IOPS     	649.42 IOPS 	0s ± 0s                   	146.737µs ± 434.261µs     	1.391898ms ± 699.148µs 
+sync test                               	Tart (--root-disk-opts="sync=none")               	0 B/s     	1.3 MB/s   	0 IOPS     	568.82 IOPS 	0s ± 0s                   	158.736µs ± 504.002µs     	1.59798ms ± 14.161331ms
+sync test                               	Tart (--root-disk-opts="caching=cached")          	0 B/s     	13 MB/s    	0 IOPS     	5.77 kIOPS  	0s ± 0s                   	26.596µs ± 832.169µs      	145.785µs ± 2.864048ms 
+sync test                               	Tart (--root-disk-opts="sync=none,caching=cached")	0 B/s     	19 MB/s    	0 IOPS     	8.37 kIOPS  	0s ± 0s                   	20.135µs ± 108.817µs      	98.274µs ± 239.631µs   
+```
+
+Host:
+
+* AWS instance: `mac2.metal` + `gp3` EBS volume
+* Hardware: Mac mini (Apple M1, 4 performance and 4 efficiency cores, 16 GB RAM, `Macmini9,1`)
+* OS: macOS Sequoia 15.0
+
+Guest:
+
+* Hardware: [Virtualization.Framework](https://developer.apple.com/documentation/virtualization)
+* OS: macOS Sequoia 15.1
+
+```
+Name                                    	Executor                                          	B/W (read)	B/W (write)	I/O (read) 	I/O (write) 	Latency (read)            	Latency (write)           	Latency (sync)         
+Single 4KiB random write process        	local                                             	0 B/s     	4.8 MB/s   	0 IOPS     	1.19 kIOPS  	0s ± 0s                   	690.818µs ± 326.595µs     	0s ± 0s                
+Single 4KiB random write process        	Tart                                              	0 B/s     	2.8 MB/s   	0 IOPS     	700.94 IOPS 	0s ± 0s                   	1.090362ms ± 918.444µs    	0s ± 0s                
+Single 4KiB random write process        	Tart (--root-disk-opts="sync=none")               	0 B/s     	3.0 MB/s   	0 IOPS     	746.23 IOPS 	0s ± 0s                   	1.028192ms ± 974.533µs    	0s ± 0s                
+Single 4KiB random write process        	Tart (--root-disk-opts="caching=cached")          	0 B/s     	4.2 MB/s   	0 IOPS     	1.04 kIOPS  	0s ± 0s                   	916.36µs ± 105.318323ms   	0s ± 0s                
+Single 4KiB random write process        	Tart (--root-disk-opts="sync=none,caching=cached")	0 B/s     	14 MB/s    	0 IOPS     	3.57 kIOPS  	0s ± 0s                   	269.796µs ± 22.419599ms   	0s ± 0s                
+16 parallel 64KiB random write processes	local                                             	0 B/s     	9.5 GB/s   	0 IOPS     	148.74 kIOPS	0s ± 0s                   	753.46µs ± 8.06509ms      	0s ± 0s                
+16 parallel 64KiB random write processes	Tart                                              	0 B/s     	5.2 GB/s   	0 IOPS     	81.46 kIOPS 	0s ± 0s                   	778.624µs ± 11.705178ms   	0s ± 0s                
+16 parallel 64KiB random write processes	Tart (--root-disk-opts="sync=none")               	0 B/s     	5.3 GB/s   	0 IOPS     	83.47 kIOPS 	0s ± 0s                   	865.448µs ± 38.369176ms   	0s ± 0s                
+16 parallel 64KiB random write processes	Tart (--root-disk-opts="caching=cached")          	0 B/s     	116 MB/s   	0 IOPS     	1.8 kIOPS   	0s ± 0s                   	37.601112ms ± 727.319309ms	0s ± 0s                
+16 parallel 64KiB random write processes	Tart (--root-disk-opts="sync=none,caching=cached")	0 B/s     	5.3 GB/s   	0 IOPS     	83.19 kIOPS 	0s ± 0s                   	900.751µs ± 51.223205ms   	0s ± 0s                
+Single 1MiB random write process        	local                                             	0 B/s     	177 MB/s   	0 IOPS     	173.27 IOPS 	0s ± 0s                   	3.833194ms ± 2.873871ms   	0s ± 0s                
+Single 1MiB random write process        	Tart                                              	0 B/s     	151 MB/s   	0 IOPS     	147.44 IOPS 	0s ± 0s                   	4.925853ms ± 7.793808ms   	0s ± 0s                
+Single 1MiB random write process        	Tart (--root-disk-opts="sync=none")               	0 B/s     	151 MB/s   	0 IOPS     	147.87 IOPS 	0s ± 0s                   	4.884797ms ± 7.563512ms   	0s ± 0s                
+Single 1MiB random write process        	Tart (--root-disk-opts="caching=cached")          	0 B/s     	72 MB/s    	0 IOPS     	69.9 IOPS   	0s ± 0s                   	8.909771ms ± 214.311644ms 	0s ± 0s                
+Single 1MiB random write process        	Tart (--root-disk-opts="sync=none,caching=cached")	0 B/s     	159 MB/s   	0 IOPS     	155.69 IOPS 	0s ± 0s                   	4.863448ms ± 88.965211ms  	0s ± 0s                
+Random reads/writes (4k)                	local                                             	8.7 MB/s  	8.7 MB/s   	2.16 kIOPS 	2.16 kIOPS  	193.353233ms ± 42.728494ms	222.325905ms ± 56.901372ms	0s ± 0s                
+Random reads/writes (4k)                	Tart                                              	3.5 MB/s  	3.5 MB/s   	862.89 IOPS	865.54 IOPS 	36.893229ms ± 12.644216ms 	37.143334ms ± 12.772017ms 	0s ± 0s                
+Random reads/writes (4k)                	Tart (--root-disk-opts="sync=none")               	3.6 MB/s  	3.6 MB/s   	907.4 IOPS 	911.55 IOPS 	35.048969ms ± 10.559354ms 	35.3046ms ± 10.67824ms    	0s ± 0s                
+Random reads/writes (4k)                	Tart (--root-disk-opts="caching=cached")          	2.7 MB/s  	2.8 MB/s   	684.11 IOPS	688.05 IOPS 	48.815322ms ± 687.806727ms	44.395556ms ± 635.532064ms	0s ± 0s                
+Random reads/writes (4k)                	Tart (--root-disk-opts="sync=none,caching=cached")	7.0 MB/s  	7.0 MB/s   	1.74 kIOPS 	1.74 kIOPS  	18.00448ms ± 93.784447ms  	18.617037ms ± 107.423001ms	0s ± 0s                
+Random reads/writes (64k)               	local                                             	121 MB/s  	121 MB/s   	1.89 kIOPS 	1.89 kIOPS  	61.983727ms ± 21.324782ms 	73.228597ms ± 12.730945ms 	0s ± 0s                
+Random reads/writes (64k)               	Tart                                              	75 MB/s   	75 MB/s    	1.17 kIOPS 	1.17 kIOPS  	26.830538ms ± 7.643051ms  	27.709602ms ± 7.830965ms  	0s ± 0s                
+Random reads/writes (64k)               	Tart (--root-disk-opts="sync=none")               	76 MB/s   	77 MB/s    	1.19 kIOPS 	1.19 kIOPS  	26.255337ms ± 7.302592ms  	27.256805ms ± 7.388266ms  	0s ± 0s                
+Random reads/writes (64k)               	Tart (--root-disk-opts="caching=cached")          	32 MB/s   	33 MB/s    	505.26 IOPS	508.66 IOPS 	65.170269ms ± 747.794957ms	61.062186ms ± 695.614904ms	0s ± 0s                
+Random reads/writes (64k)               	Tart (--root-disk-opts="sync=none,caching=cached")	79 MB/s   	79 MB/s    	1.23 kIOPS 	1.23 kIOPS  	25.861503ms ± 171.669777ms	25.992302ms ± 164.647788ms	0s ± 0s                
+sync test                               	local                                             	0 B/s     	1.9 MB/s   	0 IOPS     	865.16 IOPS 	0s ± 0s                   	100.95µs ± 268.722µs      	1.054051ms ± 365.377µs 
+sync test                               	Tart                                              	0 B/s     	1.6 MB/s   	0 IOPS     	704.13 IOPS 	0s ± 0s                   	133.886µs ± 390.263µs     	1.285085ms ± 575.27µs  
+sync test                               	Tart (--root-disk-opts="sync=none")               	0 B/s     	1.6 MB/s   	0 IOPS     	728.26 IOPS 	0s ± 0s                   	129.246µs ± 472.724µs     	1.242713ms ± 1.281286ms
+sync test                               	Tart (--root-disk-opts="caching=cached")          	0 B/s     	35 MB/s    	0 IOPS     	15.67 kIOPS 	0s ± 0s                   	11.319µs ± 24.771µs       	51.731µs ± 42.208µs    
+sync test                               	Tart (--root-disk-opts="sync=none,caching=cached")	0 B/s     	17 MB/s    	0 IOPS     	7.39 kIOPS  	0s ± 0s                   	21.23µs ± 81.749µs        	113.239µs ± 191.266µs  
+```

benchmark/internal/command/fio/benchmark.go

@@ -7,23 +7,63 @@ type Benchmark struct {
 
 var benchmarks = []Benchmark{
 	{
-		Name: "Random writing of 1MB",
-		Command: "fio --rw randwrite --runtime 30 --time_based --unlink 1 --output-format json " +
-			"--size 1MB --name unnamed --numjobs 1 --iodepth 1 --end_fsync 1",
+		// Ars Technica's "Single 4KiB random write process" test[1]
+		// with JSON output and created file cleanup
+		//
+		// [1]: https://arstechnica.com/gadgets/2020/02/how-fast-are-your-disks-find-out-the-open-source-way-with-fio/
+		Name: "Single 4KiB random write process",
+		Command: "fio --name=benchmark --ioengine=posixaio --rw=randwrite --bs=4k --size=4g --numjobs=1 --iodepth=1 --runtime=60 --time_based --end_fsync=1" +
+			" --output-format json --unlink 1",
 	},
 	{
-		Name: "Random writing of 10MB",
-		Command: "fio --rw randwrite --runtime 30 --time_based --unlink 1 --output-format json " +
-			"--size 10MB --name unnamed --numjobs 1 --iodepth 1 --end_fsync 1",
+		// Ars Technica's "16 parallel 64KiB random write processes" test[1]
+		// with JSON outpu, created file cleanup and group reporting (for
+		// easier analysis)
+		//
+		// [1]: https://arstechnica.com/gadgets/2020/02/how-fast-are-your-disks-find-out-the-open-source-way-with-fio/
+		Name: "16 parallel 64KiB random write processes",
+		Command: "fio --name=benchmark --ioengine=posixaio --rw=randwrite --bs=64k --size=256m --numjobs=16 --iodepth=16 --runtime=60 --time_based --end_fsync=1" +
+			" --output-format json --unlink 1 --group_reporting",
 	},
 	{
-		Name: "Random writing of 100MB",
-		Command: "fio --rw randwrite --runtime 30 --time_based --unlink 1 --output-format json " +
-			"--size 100MB --name unnamed --numjobs 1 --iodepth 1 --end_fsync 1",
+		// Ars Technica's "16 parallel 64KiB random write processes" test[1]
+		// with JSON output, created file cleanup and reduced file I/O size
+		// from 16 to 10 GB to avoid "No space left on device".
+		//
+		// [1]: https://arstechnica.com/gadgets/2020/02/how-fast-are-your-disks-find-out-the-open-source-way-with-fio/
+		Name: "Single 1MiB random write process",
+		Command: "fio --name=benchmark --ioengine=posixaio --rw=randwrite --bs=1m --size=10g --numjobs=1 --iodepth=1 --runtime=60 --time_based --end_fsync=1" +
+			" --output-format json --unlink 1",
 	},
 	{
-		Name: "Random writing of 1000MB",
-		Command: "fio --rw randwrite --runtime 30 --time_based --unlink 1 --output-format json " +
-			"--size 1000MB --name unnamed --numjobs 1 --iodepth 1 --end_fsync 1",
+		// Oracle's "Test random read/writes" (in IOPS Performance Tests[1]) category
+		// with JSON output, created file cleanup, without ETA newline, without custom
+		// file path, with file I/O size reduced from 500GB to 2GB to prevent
+		// "No space left on device" and with posixaio instead of libaio.
+		//
+		// [1]: https://docs.oracle.com/en-us/iaas/Content/Block/References/samplefiocommandslinux.htm#FIO_Commands
+		Name: "Random reads/writes (4k)",
+		Command: "fio --name=benchmark --size=2GB --direct=1 --rw=randrw --bs=4k --ioengine=posixaio --iodepth=256 --runtime=120 --numjobs=4 --time_based --group_reporting" +
+			" --output-format json --unlink 1",
+	},
+	{
+		// Oracle's "Test random read/writes" (in Throughput Performance Tests[1]) category
+		// with JSON output, created file cleanup, without ETA newline, without custom
+		// file path, with file I/O size reduced from 500GB to 2GB to prevent
+		// "No space left on device" and with posixaio instead of libaio.
+		//
+		// [1]: https://docs.oracle.com/en-us/iaas/Content/Block/References/samplefiocommandslinux.htm#Throughput_Performance_Tests
+		Name: "Random reads/writes (64k)",
+		Command: "fio --name=benchmark --size=2GB --direct=1 --rw=randrw --bs=64k --ioengine=posixaio --iodepth=64 --runtime=120 --numjobs=4 --time_based --group_reporting" +
+			" --output-format json --unlink 1",
+	},
+	{
+		// RedHat's "How can I test to see if my environment is fast enough for etcd"[1]
+		// with custom name
+		//
+		// [1]: https://access.redhat.com/solutions/5726511
+		Name: "sync test",
+		Command: "mkdir -p test-data && fio --name=benchmark --rw=write --ioengine=sync --fdatasync=1 --directory=test-data --size=22m --bs=2300" +
+			" --output-format json --unlink 1",
 	},
 }

benchmark/internal/command/fio/fio.go

@@ -1,20 +1,23 @@
 package fio
 
 import (
-	"context"
 	"encoding/json"
-	"errors"
 	"fmt"
-	"github.com/cirruslabs/tart/benchmark/internal/executor"
+	executorpkg "github.com/cirruslabs/tart/benchmark/internal/executor"
 	"github.com/cirruslabs/tart/benchmark/internal/executor/local"
 	"github.com/cirruslabs/tart/benchmark/internal/executor/tart"
 	"github.com/dustin/go-humanize"
 	"github.com/gosuri/uitable"
 	"github.com/spf13/cobra"
 	"go.uber.org/zap"
+	"go.uber.org/zap/zapio"
+	"os"
+	"os/exec"
 )
 
 var debug bool
+var image string
+var prepare string
 
 func NewCommand() *cobra.Command {
 	cmd := &cobra.Command{
@@ -24,6 +27,8 @@ func NewCommand() *cobra.Command {
 	}
 
 	cmd.Flags().BoolVar(&debug, "debug", false, "enable debug logging")
+	cmd.Flags().StringVar(&image, "image", "ghcr.io/cirruslabs/macos-sonoma-base:latest", "image to use for testing")
+	cmd.Flags().StringVar(&prepare, "prepare", "", "command to run before running each benchmark")
 
 	return cmd
 }
@@ -41,28 +46,95 @@ func run(cmd *cobra.Command, args []string) error {
 		_ = logger.Sync()
 	}()
 
-	executors, err := initializeExecutors(cmd.Context(), logger)
-	if err != nil {
-		return err
+	var executorInitializers = []struct {
+		Name string
+		Fn   func() (executorpkg.Executor, error)
+	}{
+		{
+			Name: "local",
+			Fn: func() (executorpkg.Executor, error) {
+				return local.New(logger)
+			},
+		},
+		{
+			Name: "Tart",
+			Fn: func() (executorpkg.Executor, error) {
+				return tart.New(cmd.Context(), image, nil, logger)
+			},
+		},
+		{
+			Name: "Tart (--root-disk-opts=\"sync=none\")",
+			Fn: func() (executorpkg.Executor, error) {
+				return tart.New(cmd.Context(), image, []string{
+					"--root-disk-opts",
+					"sync=none",
+				}, logger)
+			},
+		},
+		{
+			Name: "Tart (--root-disk-opts=\"caching=cached\")",
+			Fn: func() (executorpkg.Executor, error) {
+				return tart.New(cmd.Context(), image, []string{
+					"--root-disk-opts",
+					"caching=cached",
+				}, logger)
+			},
+		},
+		{
+			Name: "Tart (--root-disk-opts=\"sync=none,caching=cached\")",
+			Fn: func() (executorpkg.Executor, error) {
+				return tart.New(cmd.Context(), image, []string{
+					"--root-disk-opts",
+					"sync=none,caching=cached",
+				}, logger)
+			},
+		},
 	}
-	defer func() {
-		errs := []error{err}
-
-		for _, executor := range executors {
-			if err := executor.Close(); err != nil {
-				errs = append(errs, fmt.Errorf("failed to close executor %s: %w", executor.Name(), err))
-			}
-		}
-
-		err = errors.Join(errs...)
-	}()
 
 	table := uitable.New()
-	table.AddRow("Name", "Executor", "Bandwidth", "I/O operations")
+	table.AddRow("Name", "Executor", "B/W (read)", "B/W (write)", "I/O (read)", "I/O (write)",
+		"Latency (read)", "Latency (write)", "Latency (sync)")
 
 	for _, benchmark := range benchmarks {
-		for _, executor := range executors {
-			logger.Sugar().Infof("running benchmark %q on %s executor", benchmark.Name, executor.Name())
+		for _, executorInitializer := range executorInitializers {
+			if prepare != "" {
+				shell := "/bin/sh"
+
+				if shellFromEnv, ok := os.LookupEnv("SHELL"); ok {
+					shell = shellFromEnv
+				}
+
+				logger.Sugar().Infof("running prepare command %q using shell %q",
+					prepare, shell)
+
+				cmd := exec.CommandContext(cmd.Context(), shell, "-c", prepare)
+
+				loggerWriter := &zapio.Writer{Log: logger, Level: zap.DebugLevel}
+
+				cmd.Stdout = loggerWriter
+				cmd.Stderr = loggerWriter
+
+				if err := cmd.Run(); err != nil {
+					return fmt.Errorf("failed to run prepare command %q: %v", prepare, err)
+				}
+			}
+
+			logger.Sugar().Infof("initializing executor %s", executorInitializer.Name)
+
+			executor, err := executorInitializer.Fn()
+			if err != nil {
+				return err
+			}
+
+			logger.Sugar().Infof("installing Flexible I/O tester (fio) on executor %s",
+				executorInitializer.Name)
+
+			if _, err := executor.Run(cmd.Context(), "brew install fio"); err != nil {
+				return err
+			}
+
+			logger.Sugar().Infof("running benchmark %q on %s executor", benchmark.Name,
+				executorInitializer.Name)
 
 			stdout, err := executor.Run(cmd.Context(), benchmark.Command)
 			if err != nil {
@@ -82,12 +154,28 @@ func run(cmd *cobra.Command, args []string) error {
 
 			job := fioResult.Jobs[0]
 
+			readBandwidth := humanize.Bytes(uint64(job.Read.BW)*humanize.KByte) + "/s"
+			readIOPS := humanize.SIWithDigits(job.Read.IOPS, 2, "IOPS")
+
+			logger.Sugar().Infof("read bandwidth: %s, read IOPS: %s, read latency: %s",
+				readBandwidth, readIOPS, job.Read.LatencyNS.String())
+
 			writeBandwidth := humanize.Bytes(uint64(job.Write.BW)*humanize.KByte) + "/s"
 			writeIOPS := humanize.SIWithDigits(job.Write.IOPS, 2, "IOPS")
 
-			logger.Sugar().Infof("write bandwidth: %s, write IOPS: %s\n", writeBandwidth, writeIOPS)
+			logger.Sugar().Infof("write bandwidth: %s, write IOPS: %s, write latency: %s",
+				writeBandwidth, writeIOPS, job.Write.LatencyNS.String())
 
-			table.AddRow(benchmark.Name, executor.Name(), writeBandwidth, writeIOPS)
+			logger.Sugar().Infof("sync latency: %s", job.Sync.LatencyNS.String())
+
+			table.AddRow(benchmark.Name, executorInitializer.Name, readBandwidth, writeBandwidth,
+				readIOPS, writeIOPS, job.Read.LatencyNS.String(), job.Write.LatencyNS.String(),
+				job.Sync.LatencyNS.String())
+
+			if err := executor.Close(); err != nil {
+				return fmt.Errorf("failed to close executor %s: %w",
+					executorInitializer.Name, err)
+			}
 		}
 	}
 
@@ -95,37 +183,3 @@ func run(cmd *cobra.Command, args []string) error {
 
 	return nil
 }
-
-func initializeExecutors(ctx context.Context, logger *zap.Logger) ([]executor.Executor, error) {
-	var result []executor.Executor
-
-	logger.Info("initializing local executor")
-
-	local, err := local.New(logger)
-	if err != nil {
-		return nil, err
-	}
-	result = append(result, local)
-
-	logger.Info("local executor initialized")
-
-	logger.Info("initializing Tart executor")
-
-	tart, err := tart.New(ctx, logger)
-	if err != nil {
-		return nil, err
-	}
-	result = append(result, tart)
-
-	logger.Info("Tart executor initialized")
-
-	for _, executor := range result {
-		logger.Sugar().Infof("installing Flexible I/O tester (fio) on %s executor", executor.Name())
-
-		if _, err := executor.Run(ctx, "brew install fio"); err != nil {
-			return nil, err
-		}
-	}
-
-	return result, nil
-}

benchmark/internal/command/fio/json.go

@@ -1,15 +1,35 @@
 package fio
 
+import (
+	"fmt"
+	"time"
+)
+
 type Result struct {
 	Jobs []Job `json:"jobs"`
 }
 
 type Job struct {
 	Name  string `json:"jobname"`
-	Write Write  `json:"write"`
+	Read  Stats  `json:"read"`
+	Write Stats  `json:"write"`
+	Sync  Stats  `json:"sync"`
 }
 
-type Write struct {
-	BW   float64 `json:"bw"`
-	IOPS float64 `json:"iops"`
+type Stats struct {
+	BW        float64 `json:"bw"`
+	IOPS      float64 `json:"iops"`
+	LatencyNS Latency `json:"lat_ns"`
+}
+
+type Latency struct {
+	Mean   float64 `json:"mean"`
+	Stddev float64 `json:"stddev"`
+}
+
+func (latency Latency) String() string {
+	meanDuration := time.Duration(latency.Mean) * time.Nanosecond
+	stddevDuration := time.Duration(latency.Stddev) * time.Nanosecond
+
+	return fmt.Sprintf("%v ± %v", meanDuration, stddevDuration)
 }

benchmark/internal/executor/executor.go

@@ -5,7 +5,6 @@ import (
 )
 
 type Executor interface {
-	Name() string
 	Run(ctx context.Context, command string) ([]byte, error)
 	Close() error
 }

benchmark/internal/executor/tart/tart.go

@@ -8,14 +8,14 @@ import (
 	"github.com/avast/retry-go/v4"
 	"github.com/google/uuid"
 	"go.uber.org/zap"
+	"go.uber.org/zap/zapio"
 	"golang.org/x/crypto/ssh"
+	"io"
 	"net"
 	"strings"
 	"time"
 )
 
-const baseImage = "ghcr.io/cirruslabs/macos-sonoma-base:latest"
-
 type Tart struct {
 	vmRunCancel context.CancelFunc
 	vmName      string
@@ -23,17 +23,17 @@ type Tart struct {
 	logger      *zap.Logger
 }
 
-func New(ctx context.Context, logger *zap.Logger) (*Tart, error) {
+func New(ctx context.Context, image string, runArgsExtra []string, logger *zap.Logger) (*Tart, error) {
 	tart := &Tart{
 		vmName: fmt.Sprintf("tart-benchmark-%s", uuid.NewString()),
 		logger: logger,
 	}
 
-	if err := Cmd(ctx, tart.logger, "pull", baseImage); err != nil {
+	if err := Cmd(ctx, tart.logger, "pull", image); err != nil {
 		return nil, err
 	}
 
-	if err := Cmd(ctx, tart.logger, "clone", baseImage, tart.vmName); err != nil {
+	if err := Cmd(ctx, tart.logger, "clone", image, tart.vmName); err != nil {
 		return nil, err
 	}
 
@@ -41,7 +41,11 @@ func New(ctx context.Context, logger *zap.Logger) (*Tart, error) {
 	tart.vmRunCancel = vmRunCancel
 
 	go func() {
-		_ = Cmd(vmRunCtx, tart.logger, "run", "--no-graphics", tart.vmName)
+		runArgs := []string{"run", "--no-graphics", tart.vmName}
+
+		runArgs = append(runArgs, runArgsExtra...)
+
+		_ = Cmd(vmRunCtx, tart.logger, runArgs...)
 	}()
 
 	ip, err := CmdWithOutput(ctx, tart.logger, "ip", "--wait", "60", tart.vmName)
@@ -105,10 +109,12 @@ func (tart *Tart) Run(ctx context.Context, command string) ([]byte, error) {
 	}()
 	defer monitorCancel()
 
+	loggerWriter := &zapio.Writer{Log: tart.logger, Level: zap.DebugLevel}
 	stdoutBuf := &bytes.Buffer{}
 
 	sshSession.Stdin = bytes.NewBufferString(command)
-	sshSession.Stdout = stdoutBuf
+	sshSession.Stdout = io.MultiWriter(stdoutBuf, loggerWriter)
+	sshSession.Stderr = loggerWriter
 
 	if err := sshSession.Shell(); err != nil {
 		return nil, err

benchmark/internal/executor/tart/tart_test.go

@@ -11,7 +11,7 @@ import (
 func TestTart(t *testing.T) {
 	ctx := context.Background()
 
-	tart, err := tart.New(ctx, zap.NewNop())
+	tart, err := tart.New(ctx, "ghcr.io/cirruslabs/macos-sonoma-base:latest", nil, zap.NewNop())
 	require.NoError(t, err)
 
 	output, err := tart.Run(ctx, "echo \"this is a test\"")

docs/faq.md

@@ -57,7 +57,15 @@ This issue is worked around automatically [when using Softnet](http://github.com
 sudo defaults write /Library/Preferences/SystemConfiguration/com.apple.InternetSharing.default.plist bootpd -dict DHCPLeaseTimeSecs -int 600
 ```
 
-Note that this tweak persists across reboots, so normally you'll only need to do it once per new host.
+This tweak persists across reboots, so normally you'll only need to do it once per new host.
+
+If that doesn't help after starting a new VM, it's possible that the `/var/db/dhcpd_leases` file is already overfilled with 86,400-second leases. You can remove it with the following command and try starting a new VM again:
+
+```shell
+sudo rm /var/db/dhcpd_leases
+```
+
+And no worries, this file will be re-created on the next `tart run`.
 
 ## Running login/clone/pull/push commands over SSH
 
@@ -90,3 +98,21 @@ Instead of Anka Registry, Tart can work with any OCI-compatible container regist
 and scalable experience for distributing virtual machines.
 
 Tart doesn't yet have an analogue of Anka Controller for managing long living VMs but [soon will be](https://github.com/cirruslabs/tart/issues/372).
+
+## Automatic pruning
+
+`tart pull` and `tart clone` commands check the remaining space available on the volume associated with `TART_HOME` directory (defaults to `~/.tart`) before pulling or cloning anything.
+
+In case there's not enough space to fit the newly pulled or cloned VM image, Tart will remove the least recently accessed VMs from OCI cache and `.ipsw` files from IPSW cache until enough free space is available.
+
+To disable this functionality, set the `TART_NO_AUTO_PRUNE` environment variable either globally:
+
+```shell
+export TART_NO_AUTO_PRUNE=
+```
+
+...or per `tart pull` and `tart clone` invocation as follows:
+
+```shell
+TART_NO_AUTO_PRUNE= tart pull ...
+```

docs/orchard/architecture-and-security.md

@@ -0,0 +1,65 @@
+## Architecture
+
+Orchard cluster consists of two components:
+
+* Controller — responsible for managing the cluster and scheduling of resources
+* Worker — responsible for executing the VMs
+* Client — responsible for creating, modifying and removing the resources on the Controller, can either be an Orchard CLI or [an API consumer](/orchard/integration-guide)
+
+Normally you deploy a single Controller that needs to be accessible to both the Clients and Workers. Then you can deploy the Workers, which can reside anywhere and be inaccessible to Clients directly, e.g. behind a NAT.
+
+## Security
+
+When an Orchard Client or a Worker connects to the Controller, they need to establish trust and verify that they're talking to the right Controller, so that no [man-in-the-middle attack](https://en.wikipedia.org/wiki/Man-in-the-middle_attack) is possible.
+
+Similarly to web-browsers (that rely on the [public key infrastructure](https://en.wikipedia.org/wiki/Public_key_infrastructure)) and SSH (which relies on semi-automated fingerprint verification), Orchard combines these two traits in a hybrid approach by defaulting to automatic PKI verification (can be disabled by [`--no-pki`](#--no-pki-override)) and falling-back to a manual verification for self-signed certificates.
+
+This hybrid approach is needed because the Controller can be configured in two ways:
+
+* *Controller with a publicly valid certificate*
+    * can be configured manually by passing `--controller-cert` and `--controller-key` command-line arguments to `orchard controller run`
+* *Controller with a self-signed certificate*
+    * configured automatically on first Controller start-up when no `--controller-cert` and `--controller-key` command-line arguments are passed
+
+Below we'll explain how Orchard client and Worker secure the connection when accessing these two Controller types.
+
+### Client
+
+Client is associated with the Controller using a `orchard context create` command, which works as follows:
+
+* Client attempts to connect to the Controller and validate its certificate using host's root CA set (can be disabled with [`--no-pki`](#--no-pki-override))
+* if the Client encounters a  *Controller with a publicly valid certificate*, that would be the last step and the association would succeed
+* if the Client is dealing with *Controller with a self-signed certificate*, the Client will do another connection attempt to probe the Controller's certificate
+* the probed Controller's certificate fingerprint is then presented to the user, and if the user agrees to trust it, the Client then considers that certificate to be trusted for a given context
+* Client finally connects to the Controller again with a trusted CA set containing only that certificate, executes the final API sanity checks, and if everything is OK then the association succeeds
+
+Afterward, each interaction with the Controller  (e.g. `orchard create vm` command) will stick to the chosen verification method and will re-verify the presented Controller's certificate against:
+
+* *Controller with a self-signed certificate*: a trusted certificate stored in the Orchard's configuration file
+* *Controller with a publicly valid certificate*: host's root CA set
+
+### Worker
+
+To make the Worker connect to the Controller, a Bootstrap Token needs to be obtained using the `orchard get bootstrap-token` command.
+
+While this approach provides a less ad-hoc experience than that you'd have with `orchard context create`, it allows one to mass-deploy workers non-interactively, using tools such as Ansible.
+
+This resulting Bootstrap Token will either include the Controller's certificate (when the current context is with a *Controller with a self-signed certificate*) or omit it (when the current context is with a *Controller with a publicly valid certificate*).
+
+The way Worker connects to the Controller using the `orchard worker run` command is as follows:
+
+* when the Bootstrap Token contains the Controller's certificate:
+    * the Orchard Worker will try to connect to the Controller with a trusted CA set containing only that certificate
+* when the Bootstrap Token has no Controller's certificate:
+    * the Orchard Worker will try the PKI approach (can be disabled with [`--no-pki`](#--no-pki-override) to effectively prevent the Worker from connecting) and fail if certificate verification using PKI is not possible
+
+### `--no-pki` override
+
+If you only intend to access the *Controller with a self-signed certificate* and want to additionally guard yourself against [CA compromises](https://en.wikipedia.org/wiki/Certificate_authority#CA_compromise) and other PKI-specific attacks, pass a `--no-pki` command-line argument to the following commands:
+
+* `orchard context create --no-pki`
+    * this will prevent the Client from using PKI and will let you interactively verify the Controller's certificate fingerprint before connecting, thus creating a non-PKI association
+* `orchard worker run --no-pki`
+    * this will prevent the Worker from trying to use PKI when connecting to the Controller using a Bootstrap Token that has no certificate included in it, thus failing fast and letting you know that you need to create a proper Bootstrap Token
+
+We've deliberately chosen not to use environment variables (e.g. `ORCHARD_NO_PKI`) because they fail silently (e.g. due to a typo), compared to command-line arguments, which will result in an error that is much easier to detect.

docs/orchard/deploying-controller.md

@@ -0,0 +1,195 @@
+## Introduction
+
+Compared to Worker, which can only be deployed on a macOS machine, Controller can be also deployed on Linux.
+
+In fact, we've made a [container image](https://github.com/cirruslabs/orchard/pkgs/container/orchard) to ease deploying the Controller in container-native environments such as Kubernetes.
+
+Another thing to keep in mind that Orchard API is secured by default: all requests must be authenticated with the credentials of a service account. When you first run Orchard Controller, a `bootstrap-admin` service account will be created automatically and credentials will be printed to the standard output.
+
+If you already have a token in mind that you want to use for the `bootstrap-admin` service account, or you've got locked out and want this service account with a well-known password back, you can set the `ORCHARD_BOOTSTRAP_ADMIN_TOKEN` when running the controller.
+
+For example to use a secure, random value:
+
+```bash
+ORCHARD_BOOTSTRAP_ADMIN_TOKEN=$(openssl rand -hex 32) orchard controller run
+```
+
+## Deployment Methods
+
+While you can always start `orchard controller run` manually with the required arguments, this method is not recommended due to lack of persistence.
+
+In the following sections you'll find several examples of how to run Orchard Controller in various environments in a more persistent way. Feel free to submit PRs with more examples.
+
+### Google Compute Engine
+
+An example below will deploy a single instance of Orchard Controller in Google Cloud Compute Engine in `us-central1` region.
+
+First, let's create a static IP address for our instance:
+
+```bash
+gcloud compute addresses create orchard-ip --region=us-central1
+export ORCHARD_IP=$(gcloud compute addresses describe orchard-ip --format='value(address)' --region=us-central1)
+```
+
+Once we have the IP address, we can create a new instance with Orchard Controller running inside a container:
+
+```bash
+gcloud compute instances create-with-container orchard-controller \
+  --machine-type=e2-micro \
+  --zone=us-central1-a \
+  --image-family cos-stable \
+  --image-project cos-cloud \
+  --tags=https-server \
+  --address=$ORCHARD_IP \
+  --container-image=ghcr.io/cirruslabs/orchard:latest \
+  --container-env=PORT=443 \
+  --container-env=ORCHARD_BOOTSTRAP_ADMIN_TOKEN=$ORCHARD_BOOTSTRAP_ADMIN_TOKEN \
+  --container-mount-host-path=host-path=/home/orchard-data,mode=rw,mount-path=/data
+```
+
+Now you can create a new context for your local client:
+
+```bash
+orchard context create --name production \
+  --service-account-name bootstrap-admin \
+  --service-account-token $ORCHARD_BOOTSTRAP_ADMIN_TOKEN \
+  https://$ORCHARD_IP:443
+```
+
+And select it as the default context:
+
+```bash
+orchard context default production
+```
+
+### Kubernetes (GKE, EKS, etc.)
+
+The easiest way to run Orchard Controller on Kubernetes is to expose it through the `LoadBalancer` service.
+
+This way no fiddling with the TLS certificates and HTTP proxying is needed, and most cloud providers will allocate a ready-to-use IP-address that can directly used in `orchard context create` and `orchard worker run` commands, or additionally assigned to a DNS domain name for a more memorable hostname.
+
+Do deploy on Kubernetes, only three resources are needed:
+
+```yaml
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: orchard-controller
+spec:
+  accessModes:
+    - ReadWriteOnce
+  resources:
+    requests:
+      storage: 1Gi
+  # Uncomment this when deploying on Amazon's EKS and
+  # change to the desired storage class name if needed
+  # storageClassName: gp2
+---
+apiVersion: apps/v1
+kind: StatefulSet
+metadata:
+  name: orchard-controller
+spec:
+  serviceName: orchard-controller
+  replicas: 1
+  selector:
+    matchLabels:
+      app: orchard-controller
+  template:
+    metadata:
+      labels:
+        app: orchard-controller
+    spec:
+      containers:
+        - name: orchard-controller
+          image: ghcr.io/cirruslabs/orchard:latest
+          volumeMounts:
+            - mountPath: /data
+              name: orchard-controller
+      volumes:
+        - name: orchard-controller
+          persistentVolumeClaim:
+            claimName: orchard-controller
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: orchard-controller
+spec:
+  selector:
+    app: orchard-controller
+  ports:
+    - protocol: TCP
+      port: 6120
+      targetPort: 6120
+  type: LoadBalancer
+```
+
+Once deployed, the bootstrap credentials will be printed to the standard output. You can inspect them by running `kubectl logs deployment/orchard-controller`.
+
+The resources above ensure that Controller's database is stored in a persistent storage and survives restats.
+
+You can further allocate a static IP address and use it by adding annotations to the `Service` resource. Here's how to do that:
+
+* on Google's GKE: <https://cloud.google.com/kubernetes-engine/docs/concepts/service-load-balancer-parameters#spd-static-ip>
+* on Amazon's EKS: <https://kubernetes.io/docs/reference/labels-annotations-taints/#service-beta-kubernetes-io-aws-load-balancer-eip-allocations>
+
+### systemd service on Debian-based distributions
+
+This should work for most Debian-based distributions like Debian, Ubuntu, etc.
+
+Firstly, make sure that the APT transport for downloading packages via HTTPS and common X.509 certificates are installed:
+
+```shell
+sudo apt-get update && sudo apt-get -y install apt-transport-https ca-certificates
+```
+
+Then, add the Cirrus Labs repository:
+
+```shell
+echo "deb [trusted=yes] https://apt.fury.io/cirruslabs/ /" | sudo tee /etc/apt/sources.list.d/cirruslabs.list
+```
+
+Update the package index files and install the Orchard Controller:
+
+```shell
+sudo apt-get update && sudo apt-get -y install orchard-controller
+```
+
+Finally, enable and start the Orchard Controller systemd service:
+
+```shell
+sudo systemctl enable orchard-controller
+sudo systemctl start orchard-controller
+```
+
+The bootstrap credentials will be printed to the standard output. You can inspect them by running `sudo systemctl status orhcard-controller` or `journalctl -u orchard-controller`.
+
+### systemd service on RPM-based distributions
+
+This should work for most RPM-based distributions like Fedora, CentOS, etc.
+
+First, create a `/etc/yum.repos.d/cirruslabs.repo` file with the following contents:
+
+```ini
+[cirruslabs]
+name=Cirrus Labs Repo
+baseurl=https://yum.fury.io/cirruslabs/
+enabled=1
+gpgcheck=0
+```
+
+Then, install the Orchard Controller:
+
+```shell
+sudo yum -y install orchard-controller
+```
+
+Finally, enable and start the Orchard Controller systemd service:
+
+```shell
+systemctl enable orchard-controller
+systemctl start orchard-controller
+```
+
+The bootstrap credentials will be printed to the standard output. You can inspect them by running `sudo systemctl status orhcard-controller` or `journalctl -u orchard-controller`.

docs/orchard/deploying-workers.md

@@ -0,0 +1,127 @@
+## Obtain a Boostrap Token
+
+First, create a service account with a minimal set of roles (`compute:read` and `compute:write`) required for proper Worker functioning:
+
+```bash
+orchard create service-account worker-pool-m1 --roles "compute:read" --roles "compute:write"
+```
+
+Then, generate a Bootstrap Token for this service account:
+
+```shell
+orchard get bootstrap-token worker-pool-m1
+```
+
+We will reference the value of the Bootstrap Token generated here as `${BOOTSTRAP_TOKEN}` below.
+
+Further, we assume that Orchard controller is available on `orchard.example.com`
+
+## Deployment Methods
+
+While you can always run `orchard worker run` manually with the required arguments, this method of deploying the Worker is not recommended.
+
+Instead, we've listed a more persistent methods of a Worker deployment below.
+
+### launchd
+
+[launchd](https://launchd.info/) is an init system for macOS that manages daemons, agents and other background processes.
+
+In this deployment method, we'll create a new job definition file for the launchd to manage on its behalf.
+
+To begin, first install Orchard:
+
+```shell
+brew install cirruslabs/cli/orchard
+```
+
+Ensure that the following command:
+
+```shell
+which orchard
+```
+
+...yields `/opt/homebrew/bin/orchard`. If not, you'll need to replace all of the occurences of `/opt/homebrew/bin/orchard` in the job definition below.
+
+Then, create a launchd job definition in `/Library/LaunchDaemons/org.cirruslabs.orchard.worker.plist` with the following contents:
+
+```xml
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+  <dict>
+    <key>Label</key>
+    <string>org.cirruslabs.orchard.worker</string>
+    <key>UserName</key>
+    <string>admin</string>
+    <key>Program</key>
+    <string>/opt/homebrew/bin/orchard</string>
+    <key>ProgramArguments</key>
+    <array>
+      <string>/opt/homebrew/bin/orchard</string>
+      <string>worker</string>
+      <string>run</string>
+      <string>--bootstrap-token</string>
+      <string>${BOOTSTRAP_TOKEN}</string>
+      <string>orchard.example.com</string>
+    </array>
+    <key>EnvironmentVariables</key>
+    <dict>
+      <key>PATH</key>
+      <string>/bin:/usr/bin:/usr/local/bin:/opt/homebrew/bin</string>
+    </dict>
+    <key>WorkingDirectory</key>
+    <string>/var/empty</string>
+    <key>RunAtLoad</key>
+    <true/>
+    <key>KeepAlive</key>
+    <true/>
+    <key>StandardOutPath</key>
+    <string>/Users/admin/orchard-launchd.log</string>
+    <key>StandardErrorPath</key>
+    <string>/Users/admin/orchard-launchd.log</string>
+  </dict>
+</plist>
+```
+
+This assumes that your macOS user on the host is named `admin`. If not, change all occurrences of `admin` in the job definition above to `$USER`.
+
+Finally, change the `orchard.example.com` to the FQDN or an IP-address of your Orchard Controller.
+
+Now, you can start the job:
+
+```shell
+launchctl load -w /Library/LaunchDaemons/org.cirruslabs.orchard.worker.plist
+```
+
+### Ansible
+
+If you have a set of machines that you want to use as Orchard Workers, you can use [Ansible](https://docs.ansible.com/) to configure them.
+
+We've created the [cirruslabs/ansible-orchard](https://github.com/cirruslabs/ansible-orchard) repository with a basic Ansible playbook for convenient setup.
+
+To use it, clone it locally:
+
+```shell
+git clone https://github.com/cirruslabs/ansible-orchard.git
+cd ansible-orchard/
+```
+
+Make sure that the Ansible Galaxy dependencies are installed:
+
+```shell
+ansible-galaxy install -r requirements.yml
+```
+
+Then, edit the `production-pool` file and populate the following fields:
+
+* `hosts` — replace `worker-1.hosts.internal` with your worker FQDN or IP-address and add more hosts if needed
+* `ansible_user` — set it macOS user on the host for the SSH to work
+* `orchard_worker_user` — set it macOS user on the host under which the Worker will run, e.g. `admin`
+* `orchard_worker_controller_url` — set it to FQDN or an IP-address of your Orchard Controller, for example, `orchard.example.com`
+* `orchard_worker_bootstrap_token` — set it to `${BOOTSTRAP_TOKEN}` we've generated above
+
+Deploy the playbook:
+
+```shell
+ansible-playbook --inventory-file production-pool --ask-pass playbook-workers.yml
+```

docs/orchard/integration-guide.md

@@ -0,0 +1,187 @@
+Orchard has a REST API that follows [OpenAPI specification](https://swagger.io/specification/) and is described in [`api/openapi.yaml`](https://github.com/cirruslabs/orchard/blob/main/api/openapi.yaml).
+
+You can run `orchard dev` locally and navigate to `http://127.0.0.1:6120/v1/` for interactive documentation.
+
+![](/assets/images/orchard/orchard-api-documentation-browser.png)
+
+## Using the API
+
+Below you'll find examples of using Orchard API via vanilla Python's request library and Golang package that Orchard CLI build on top of.
+
+### Authentication
+
+When running in non-development mode, Orchard API expects a [basic access authentication](https://en.wikipedia.org/wiki/Basic_access_authentication) to be provided for each API call.
+
+Below you'll find two snippets that retrieve controller's information and output its version:
+
+#### Authentication in Python
+
+```python
+import requests
+from requests.auth import HTTPBasicAuth
+
+
+def main():
+  # Authentication
+  basic_auth = HTTPBasicAuth("service account name", "service account token")
+
+  response = requests.get("http://127.0.0.1:6120/v1/info", auth=basic_auth)
+
+  print(response.json()["version"])
+
+
+if __name__ == '__main__':
+  main()
+```
+
+#### Authentication in Golang
+
+```go
+package main
+
+import (
+  "context"
+  "fmt"
+  "github.com/cirruslabs/orchard/pkg/client"
+  "log"
+)
+
+func main() {
+  client, err := client.New()
+  if err != nil {
+    log.Fatalf("failed to initialize Orchard API client: %v", err)
+  }
+
+  controllerInfo, err := client.Controller().Info(context.Background())
+  if err != nil {
+    log.Fatalf("failed to retrieve controller's information: %v", err)
+  }
+
+  fmt.Println(controllerInfo.Version)
+}
+```
+
+Note that we don't provide any credentials for Golang's version of the snippet: this is because Orchard's Golang API client (`github.com/cirruslabs/orchard/pkg/client`) has the ability to read the current's user Orchard context automatically.
+
+### Creating a VM
+
+A more intricate example would be spinning off a VM with a startup script that outputs date, reading its logs and removing it from the controller:
+
+#### Creating a VM in Python
+
+```python
+import time
+import uuid
+
+import requests
+from requests.auth import HTTPBasicAuth
+
+
+def main():
+  vm_name = str(uuid.uuid4())
+
+  basic_auth = HTTPBasicAuth("service account name", "service account token")
+
+  # Create VM
+  response = requests.post("http://127.0.0.1:6120/v1/vms", auth=basic_auth, json={
+    "name": vm_name,
+    "image": "ghcr.io/cirruslabs/macos-sonoma-base:latest",
+    "cpu": 4,
+    "memory": 4096,
+    "startup_script": {
+      "script_content": "date",
+    }
+  })
+  response.raise_for_status()
+
+  # Retrieve VM's logs
+  while True:
+    response = requests.get(f"http://127.0.0.1:6120/v1/vms/{vm_name}/events", auth=basic_auth)
+    response.raise_for_status()
+
+    result = response.json()
+
+    if isinstance(result, list) and len(result) != 0:
+      print(result[0]["payload"])
+      break
+
+    time.sleep(1)
+
+  # Delete VM
+  response = requests.delete(f"http://127.0.0.1:6120/v1/vms/{vm_name}", auth=basic_auth)
+  response.raise_for_status()
+
+
+if __name__ == '__main__':
+  main()
+```
+
+#### Creating a VM in Golang
+
+```go
+package main
+
+import (
+  "context"
+  "fmt"
+  "github.com/cirruslabs/orchard/pkg/client"
+  v1 "github.com/cirruslabs/orchard/pkg/resource/v1"
+  "github.com/google/uuid"
+  "log"
+  "time"
+)
+
+func main() {
+  vmName := uuid.New().String()
+
+  client, err := client.New()
+  if err != nil {
+    log.Fatalf("failed to initialize Orchard API client: %v", err)
+  }
+
+  // Create VM
+  err = client.VMs().Create(context.Background(), &v1.VM{
+    Meta: v1.Meta{
+      Name: vmName,
+    },
+    Image:  "ghcr.io/cirruslabs/macos-sonoma-base:latest",
+    CPU:    4,
+    Memory: 4096,
+    StartupScript: &v1.VMScript{
+      ScriptContent: "date",
+    },
+  })
+  if err != nil {
+    log.Fatalf("failed to create VM: %v")
+  }
+
+  // Retrieve VM's logs
+  for {
+    vmLogs, err := client.VMs().Logs(context.Background(), vmName)
+    if err != nil {
+      log.Fatalf("failed to retrieve VM logs")
+    }
+
+    if len(vmLogs) != 0 {
+      fmt.Println(vmLogs[0])
+      break
+    }
+
+    time.Sleep(time.Second)
+  }
+
+  // Delete VM
+  if err := client.VMs().Delete(context.Background(), vmName); err != nil {
+    log.Fatalf("failed to delete VM: %v", err)
+  }
+}
+```
+
+## Resource management
+
+Some resources, such as `Worker` and `VM`, have a `resource` field which is a dictionary that maps between resource names and their amounts (amount requested or amount provided, depending on the resource) and is useful for scheduling.
+
+Well-known resources:
+
+* `org.cirruslabs.tart-vms` — number of Tart VM slots available on the machine or requested by the VM
+    * this number is `2` for workers and `1` for VMs by default

docs/orchard/managing-cluster.md

@@ -0,0 +1,30 @@
+## Backups
+
+In order to backup the Orchard Controller, simply copy its `ORCHARD_HOME` (which defaults to `~/.orchard/`) directory somewhere safe and restore it when needed.
+
+This directory contains a BadgerDB database that Controller uses to store state and an X.509 certificate with key.
+
+## Upgrades
+
+Since the Orchard's initial release, we've managed to maintain the backwards compatibility between versions up to this day, so generally, it doesn't matter whether you upgrade the Controller or Worker(s) first.
+
+In case a new functionality is introduced, you might be required to finish the upgrade of both the Controller and the Worker(s) to be able to use it fully.
+
+In case there will be backwards-incompatible changes introduced in the future, we will try to do our best and highlight this in the [release notes](https://github.com/cirruslabs/orchard/releases) accordingly.
+
+## Observability
+
+Both the Controller and Worker produce some useful OpenTelemetry metrics. Metrics are scoped with `org.cirruslabs.orchard` prefix and include information about resource utilization, statuses or Workers, scheduling/pull time and many more.
+
+By default, the telemetry is sent to `https://localhost:4317` using the gRPC protocol and to `http://localhost:4318` using the HTTP protocol.
+
+You can override this by setting the [standard OpenTelemetry environment variable](https://opentelemetry.io/docs/specs/otel/configuration/sdk-environment-variables/) `OTEL_EXPORTER_OTLP_ENDPOINT`.
+
+Please refer to [OTEL Collector documentation](https://opentelemetry.io/docs/collector/) for instruction on how to setup a sidecar for the metrics collections or find out if your SaaS monitoring has an available OTEL endpoint (see [Honeycomb](https://docs.honeycomb.io/send-data/opentelemetry/) as an example).
+
+### Sending metrics to Google Cloud Platform
+
+There are two standard options of ingesting metrics procuded by Orchard Controller and Workers into the GCP:
+
+* [OpenTelemetry Collector](https://opentelemetry.io/docs/collector/) + [Google Cloud Exporter](https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/main/exporter/googlecloudexporter/README.md) — open-source solution that can be later re-purposed to send metrics to any OTLP-compatible endpoint by swapping a single [exporter](https://opentelemetry.io/docs/collector/configuration/#exporters)
+* [Ops Agent](https://cloud.google.com/monitoring/agent/ops-agent/otlp) — Google-backed solution with a syntax similar to OpenTelemetry Collector, but tied to GCP-only

docs/orchard/quick-start.md

@@ -0,0 +1,101 @@
+Tart is great for running workloads on a single machine, but what if you have more than one computer at your disposal
+and
+a couple of VMs is not enough anymore for your needs? This is where [Orchard](https://github.com/cirruslabs/orchard)
+comes in to play!
+
+It allows you to orchestrate multiple Tart-capable hosts from either an Orchard CLI (which we demonstrate below)
+or [through the API](/orchard/integration-guide).
+
+The easiest way to start is to run Orchard in local development mode:
+
+```shell
+brew install cirruslabs/cli/orchard
+orchard dev
+```
+
+This will run an Orchard Controller and an Orchard Worker in a single process on your local machine, allowing you to
+test both the CLI functionality and the API from a tool like cURL or programming language of choice, without the need to
+authenticate requests.
+
+Note that in production deployments, these two components are started separately and enable security by default. Please
+refer to [Deploying Controller](/orchard/deploying-controller) and [Deploying Workers](/orchard/deploying-workers) for
+more information.
+
+## Creating Virtual Machines
+
+Now, let's create a Virtual Machine:
+
+```shell
+orchard create vm --image ghcr.io/cirruslabs/macos-sonoma-base:latest sonoma-base
+```
+
+You can check a list of VM resources to see if the Virtual Machine we've created above is already running:
+
+```shell
+orchard list vms
+```
+
+## Accessing Virtual Machines
+
+Orchard has an ability to do port forwarding that `ssh` and `vnc` commands are built on top of. All port forwarding
+connections are done via the Orchard Controller instance which "proxies" a secure connection to the Orchard Workers.
+
+Therefore, your workers can be located under a stricter firewall that only allows connections to the Orchard Controller
+instance. Orchard Controller instance is secured by default and all API calls are authenticated and authorized.
+
+### SSH
+
+To SSH into a VM, use the `orchard ssh` command:
+
+```shell
+orchard ssh vm sonoma-base
+```
+
+You can specify the `--username` and `--password` flags to specify the username/password pair to use for the SSH
+protocol. By default, `admin`/`admin` is used.
+
+You can also execute remote commands instead of spawning a login shell, similarly to how OpenSSH's `ssh` command accepts
+a command argument:
+
+```shell
+orchard ssh vm sonoma-base "uname -a"
+```
+
+You can execute scripts remotely this way, by telling the remote command-line interpreter to read from the standard
+input and using the redirection operator as follows:
+
+```shell
+orchard ssh vm sonoma-base "bash -s" < script.sh
+```
+
+### VNC
+
+Similarly to `ssh` command, you can use `vnc` command to open Screen Sharing into a remote VM:
+
+```shell
+orchard vnc vm sonoma-base
+```
+
+You can specify the `--username` and `--password` flags to specify the username/password pair to use for the VNC
+protocol. By default, `admin`/`admin` is used.
+
+## Deleting Virtual Machines
+
+The following command will delete the VM we've created above and clean-up the resources associated with it:
+
+```shell
+orchard delete vm sonoma-base
+```
+
+## Environment variables
+
+In addition to controlling the Orchard via the CLI arguments, there are environment variables that may be beneficial
+both when automating Orchard and in daily use:
+
+| Variable name                   | Description                                                                                                                                                                                                                                                                                                                                                                  |
+|---------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| `ORCHARD_HOME`                  | Override Orchard's home directory. Useful when running multiple Orchard instances on the same host and when testing.                                                                                                                                                                                                                                                         |
+| `ORCHARD_LICENSE_TIER`          | The default license limit only allows connecting 4 Orchard Workers to the Orchard Controller. If you've purchased a [Gold Tier License](/licensing/), set this variable to `gold` to increase the limit to 20 Orchard Workers. And if you've purchased a [Platinum Tier License](/licensing/), set this variable to `platinum` to increase the limit to 200 Orchard Workers. |
+| `ORCHARD_URL`                   | Override controller URL on per-command basis.                                                                                                                                                                                                                                                                                                                                |
+| `ORCHARD_SERVICE_ACCOUNT_NAME`  | Override service account name (used for controller API auth) on per-command basis.                                                                                                                                                                                                                                                                                           |
+| `ORCHARD_SERVICE_ACCOUNT_TOKEN` | Override service account token (used for controller API auth) on per-command basis.                                                                                                                                                                                                                                                                                          |

mkdocs.yml

@@ -91,13 +91,19 @@ nav:
   - "Home": index.md
   - "Quick Start": quick-start.md
   - "Integrations":
-    - "Self-hosted CI": integrations/cirrus-cli.md
-    - "GitHub Actions": https://cirrus-runners.app/
-    - "GitLab Runner": integrations/gitlab-runner.md
-    - "Buildkite": integrations/buildkite.md
-    - "Managing VMs": integrations/vm-management.md
+      - "Self-hosted CI": integrations/cirrus-cli.md
+      - "GitHub Actions": https://cirrus-runners.app/
+      - "GitLab Runner": integrations/gitlab-runner.md
+      - "Buildkite": integrations/buildkite.md
+      - "Managing VMs": integrations/vm-management.md
   - "Support & Licensing": licensing.md
-  - "Orchestration": https://github.com/cirruslabs/orchard
+  - "Orchestration":
+      - "Quick Start": orchard/quick-start.md
+      - "Architecture and Security": orchard/architecture-and-security.md
+      - "Deploying Controller": orchard/deploying-controller.md
+      - "Deploying Workers": orchard/deploying-workers.md
+      - "Managing the Cluster": orchard/managing-cluster.md
+      - "Integrating with the API": orchard/integration-guide.md
   - "FAQ": faq.md
   - "Legal":
       - 'Terms of Service': legal/terms.md