From 5d58314a1678e4d489bb6c937f0d2de74c1f1a99 Mon Sep 17 00:00:00 2001
From: Sergey Dudoladov <sergey.dudoladov@zalando.de>
Date: Tue, 22 Sep 2020 14:09:06 +0200
Subject: [PATCH] compare Postgres pod priority on Sync

---
 manifests/configmap.yaml                   |  1 +
 manifests/postgres-pod-priority-class.yaml | 11 +++++++++++
 pkg/cluster/cluster.go                     | 14 ++++++++++++++
 3 files changed, 26 insertions(+)
 create mode 100644 manifests/postgres-pod-priority-class.yaml

diff --git a/manifests/configmap.yaml b/manifests/configmap.yaml
index db39ee33c..998e0e45f 100644
--- a/manifests/configmap.yaml
+++ b/manifests/configmap.yaml
@@ -85,6 +85,7 @@ data:
   pod_service_account_name: "postgres-pod"
   # pod_service_account_role_binding_definition: ""
   pod_terminate_grace_period: 5m
+  # pod_priority_class_name: "postgres-pod-priority"
   # postgres_superuser_teams: "postgres_superusers"
   # protected_role_names: "admin"
   ready_wait_interval: 3s
diff --git a/manifests/postgres-pod-priority-class.yaml b/manifests/postgres-pod-priority-class.yaml
new file mode 100644
index 000000000..f1b565f21
--- /dev/null
+++ b/manifests/postgres-pod-priority-class.yaml
@@ -0,0 +1,11 @@
+apiVersion: scheduling.k8s.io/v1
+description: 'This priority class must be used only for databases controlled by the
+  Postgres operator'
+kind: PriorityClass
+metadata:
+  labels:
+    application: postgres-operator
+  name: postgres-pod-priority
+preemptionPolicy: PreemptLowerPriority
+globalDefault: false
+value: 1000000
diff --git a/pkg/cluster/cluster.go b/pkg/cluster/cluster.go
index 51c5d3809..bf4a56be3 100644
--- a/pkg/cluster/cluster.go
+++ b/pkg/cluster/cluster.go
@@ -459,6 +459,20 @@ func (c *Cluster) compareStatefulSetWith(statefulSet *appsv1.StatefulSet) *compa
 		}
 	}
 
+	if c.Statefulset.Spec.Template.Spec.PriorityClassName != statefulSet.Spec.Template.Spec.PriorityClassName {
+		match = false
+		needsReplace = true
+		needsRollUpdate = true
+		reasons = append(reasons, "new statefulset's pod priority class in spec doesn't match the current one")
+	}
+
+	if c.Statefulset.Spec.Template.Spec.Priority != statefulSet.Spec.Template.Spec.Priority {
+		match = false
+		needsReplace = true
+		needsRollUpdate = true
+		reasons = append(reasons, "new statefulset's pod priority value in spec doesn't match the current one")
+	}
+
 	// lazy Spilo update: modify the image in the statefulset itself but let its pods run with the old image
 	// until they are re-created for other reasons, for example node rotation
 	if c.OpConfig.EnableLazySpiloUpgrade && !reflect.DeepEqual(c.Statefulset.Spec.Template.Spec.Containers[0].Image, statefulSet.Spec.Template.Spec.Containers[0].Image) {