[ws-daemon] Improve cgroup plugin activation count

Author: csweichel

components/ws-daemon/pkg/cgroup/cgroup.go

@@ -92,7 +92,7 @@ func (host *PluginHost) WorkspaceAdded(ctx context.Context, ws *dispatch.Workspa
 		go func(plg Plugin) {
 			err := plg.Apply(ctx, host.CGroupBasePath, cgroupPath)
 			if err == context.Canceled || err == context.DeadlineExceeded {
-				return
+				err = nil
 			}
 			if err != nil {
 				log.WithError(err).WithFields(ws.OWI()).WithField("plugin", plg.Name()).Error("cgroup plugin failure")

components/ws-daemon/pkg/cgroup/plugin_iolimit_v2.go

@@ -26,34 +26,37 @@ func (c *IOLimiterV2) Name() string  { return "iolimiter-v2" }
 func (c *IOLimiterV2) Type() Version { return Version2 }
 
 func (c *IOLimiterV2) Apply(ctx context.Context, basePath, cgroupPath string) error {
-	// We are racing workspacekit and the interaction with disks.
-	// If we did this just once there's a chance we haven't interacted with all
-	// devices yet, and hence would not impose IO limits on them.
-	ticker := time.NewTicker(30 * time.Second)
-	defer ticker.Stop()
-	for {
-		select {
-		case <-ctx.Done():
-			// Prior to shutting down though, we need to reset the IO limits to ensure we don't have
-			// processes stuck in the uninterruptable "D" (disk sleep) state. This would prevent the
-			// workspace pod from shutting down.
-			c.WriteBytesPerSecond = 0
-			c.ReadBytesPerSecond = 0
-			c.WriteIOPs = 0
-			c.ReadIOPs = 0
+	go func() {
+		// We are racing workspacekit and the interaction with disks.
+		// If we did this just once there's a chance we haven't interacted with all
+		// devices yet, and hence would not impose IO limits on them.
+		ticker := time.NewTicker(30 * time.Second)
+		defer ticker.Stop()
+		for {
+			select {
+			case <-ctx.Done():
+				// Prior to shutting down though, we need to reset the IO limits to ensure we don't have
+				// processes stuck in the uninterruptable "D" (disk sleep) state. This would prevent the
+				// workspace pod from shutting down.
+				c.WriteBytesPerSecond = 0
+				c.ReadBytesPerSecond = 0
+				c.WriteIOPs = 0
+				c.ReadIOPs = 0
 
-			err := c.writeIOMax(filepath.Join(basePath, cgroupPath))
-			if err != nil {
-				return err
-			}
-			return ctx.Err()
-		case <-ticker.C:
-			err := c.writeIOMax(filepath.Join(basePath, cgroupPath))
-			if err != nil {
-				log.WithError(err).WithField("cgroupPath", cgroupPath).Error("cannot write IO limits")
+				err := c.writeIOMax(filepath.Join(basePath, cgroupPath))
+				if err != nil {
+					log.WithError(err).WithField("cgroupPath", cgroupPath).Error("cannot write IO limits")
+				}
+				return
+			case <-ticker.C:
+				err := c.writeIOMax(filepath.Join(basePath, cgroupPath))
+				if err != nil {
+					log.WithError(err).WithField("cgroupPath", cgroupPath).Error("cannot write IO limits")
+				}
 			}
 		}
-	}
+	}()
+	return nil
 }
 
 func (c *IOLimiterV2) writeIOMax(loc string) error {