controller: cleanup complete deployments only

Signed-off-by: Michail Kargakis <mkargaki@redhat.com>

pkg/controller/deployment/deployment_controller.go

@@ -614,25 +614,6 @@ func (dc *DeploymentController) syncDeployment(key string) error {
 		return dc.syncStatusOnly(d, rsList, podMap)
 	}
 
-	// Why run the cleanup policy only when there is no rollback request?
-	// The thing with the cleanup policy currently is that it is far from smart because it takes into account
-	// the latest replica sets while it should instead retain the latest *working* replica sets. This means that
-	// you can have a cleanup policy of 1 but your last known working replica set may be 2 or 3 versions back
-	// in the history.
-	// Eventually we will want to find a way to recognize replica sets that have worked at some point in time
-	// (and chances are higher that they will work again as opposed to others that didn't) for candidates to
-	// automatically roll back to (#23211) and the cleanup policy should help.
-	if d.Spec.RollbackTo == nil {
-		_, oldRSs, err := dc.getAllReplicaSetsAndSyncRevision(d, rsList, podMap, false)
-		if err != nil {
-			return err
-		}
-		// So far the cleanup policy was executed once a deployment was paused, scaled up/down, or it
-		// successfully completed deploying a replica set. Decouple it from the strategies and have it
-		// run almost unconditionally - cleanupDeployment is safe by default.
-		dc.cleanupDeployment(oldRSs, d)
-	}
-
 	// Update deployment conditions with an Unknown condition when pausing/resuming
 	// a deployment. In this way, we can be sure that we won't timeout when a user
 	// resumes a Deployment with a set progressDeadlineSeconds.

pkg/controller/deployment/recreate.go

@@ -63,6 +63,12 @@ func (dc *DeploymentController) rolloutRecreate(d *extensions.Deployment, rsList
 		return err
 	}
 
+	if util.DeploymentComplete(d, &d.Status) {
+		if err := dc.cleanupDeployment(oldRSs, d); err != nil {
+			return err
+		}
+	}
+
 	// Sync deployment status.
 	return dc.syncRolloutStatus(allRSs, newRS, d)
 }

pkg/controller/deployment/rolling.go

@@ -57,6 +57,12 @@ func (dc *DeploymentController) rolloutRolling(d *extensions.Deployment, rsList
 		return dc.syncRolloutStatus(allRSs, newRS, d)
 	}
 
+	if deploymentutil.DeploymentComplete(d, &d.Status) {
+		if err := dc.cleanupDeployment(oldRSs, d); err != nil {
+			return err
+		}
+	}
+
 	// Sync deployment status
 	return dc.syncRolloutStatus(allRSs, newRS, d)
 }

pkg/controller/deployment/sync.go

@@ -59,6 +59,13 @@ func (dc *DeploymentController) sync(d *extensions.Deployment, rsList []*extensi
 		return err
 	}
 
+	// Clean up the deployment when it's paused and no rollback is in flight.
+	if d.Spec.Paused && d.Spec.RollbackTo == nil {
+		if err := dc.cleanupDeployment(oldRSs, d); err != nil {
+			return err
+		}
+	}
+
 	allRSs := append(oldRSs, newRS)
 	return dc.syncDeploymentStatus(allRSs, newRS, d)
 }
@@ -552,7 +559,6 @@ func (dc *DeploymentController) cleanupDeployment(oldRSs []*extensions.ReplicaSe
 	sort.Sort(controller.ReplicaSetsByCreationTimestamp(cleanableRSes))
 	glog.V(4).Infof("Looking to cleanup old replica sets for deployment %q", deployment.Name)
 
-	var errList []error
 	for i := int32(0); i < diff; i++ {
 		rs := cleanableRSes[i]
 		// Avoid delete replica set with non-zero replica counts
@@ -561,12 +567,13 @@ func (dc *DeploymentController) cleanupDeployment(oldRSs []*extensions.ReplicaSe
 		}
 		glog.V(4).Infof("Trying to cleanup replica set %q for deployment %q", rs.Name, deployment.Name)
 		if err := dc.client.Extensions().ReplicaSets(rs.Namespace).Delete(rs.Name, nil); err != nil && !errors.IsNotFound(err) {
-			glog.V(2).Infof("Failed deleting old replica set %v for deployment %v: %v", rs.Name, deployment.Name, err)
-			errList = append(errList, err)
+			// Return error instead of aggregating and continuing DELETEs on the theory
+			// that we may be overloading the api server.
+			return err
 		}
 	}
 
-	return utilerrors.NewAggregate(errList)
+	return nil
 }
 
 // syncDeploymentStatus checks if the status is up-to-date and sync it if necessary