Remove tarball.WithCompressedCaching flag to resolve OOM Killed error (#1722)

* Remove tarball.WithCompressedCaching flag to resolve OOM Killed error

Large images cannot be build as the kaniko container will be killed due to an OOM error. Removing the tarball compression drastically reduces the memory required to push large image layers. Fixes #1680

This change may increase the build time for smaller images. Therefore a command line option to trigger the compression or a more intelligent behaviour may be useful.

* Add new command line flag to toggle compressed caching

* Add unittest for build with --compressed-caching command line flag set to false

pkg/executor/build.go

@@ -477,7 +477,12 @@ func (s *stageBuilder) saveSnapshotToLayer(tarPath string) (v1.Layer, error) {
 		return nil, nil
 	}
 
-	layer, err := tarball.LayerFromFile(tarPath, tarball.WithCompressedCaching)
+	var layer v1.Layer
+	if s.opts.CompressedCaching == true {
+		layer, err = tarball.LayerFromFile(tarPath, tarball.WithCompressedCaching)
+	} else {
+		layer, err = tarball.LayerFromFile(tarPath)
+	}
 	if err != nil {
 		return nil, err
 	}

pkg/executor/build_test.go

@@ -784,6 +784,42 @@ func Test_stageBuilder_build(t *testing.T) {
 				rootDir:           dir,
 			}
 		}(),
+		func() testcase {
+			dir, files := tempDirAndFile(t)
+			file := files[0]
+			filePath := filepath.Join(dir, file)
+			ch := NewCompositeCache("", "meow")
+
+			ch.AddPath(filePath, util.FileContext{})
+			hash, err := ch.Hash()
+			if err != nil {
+				t.Errorf("couldn't create hash %v", err)
+			}
+			command := MockDockerCommand{
+				command:      "meow",
+				contextFiles: []string{filePath},
+				cacheCommand: MockCachedDockerCommand{
+					contextFiles: []string{filePath},
+				},
+			}
+
+			destDir, err := ioutil.TempDir("", "baz")
+			if err != nil {
+				t.Errorf("could not create temp dir %v", err)
+			}
+			return testcase{
+				description: "fake command cache enabled with tar compression disabled and key in cache",
+				opts:        &config.KanikoOptions{Cache: true, CompressedCaching: false},
+				config:      &v1.ConfigFile{Config: v1.Config{WorkingDir: destDir}},
+				layerCache: &fakeLayerCache{
+					retrieve: true,
+				},
+				expectedCacheKeys: []string{hash},
+				pushedCacheKeys:   []string{},
+				commands:          []commands.DockerCommand{command},
+				rootDir:           dir,
+			}
+		}(),
 		{
 			description: "fake command cache disabled and key not in cache",
 			opts:        &config.KanikoOptions{Cache: false},

pkg/executor/push.go

@@ -327,7 +327,13 @@ func writeImageOutputs(image v1.Image, destRefs []name.Tag) error {
 // pushLayerToCache pushes layer (tagged with cacheKey) to opts.Cache
 // if opts.Cache doesn't exist, infer the cache from the given destination
 func pushLayerToCache(opts *config.KanikoOptions, cacheKey string, tarPath string, createdBy string) error {
-	layer, err := tarball.LayerFromFile(tarPath, tarball.WithCompressedCaching)
+	var layer v1.Layer
+	var err error
+	if opts.CompressedCaching == true {
+		layer, err = tarball.LayerFromFile(tarPath, tarball.WithCompressedCaching)
+	} else {
+		layer, err = tarball.LayerFromFile(tarPath)
+	}
 	if err != nil {
 		return err
 	}