Add note on dynamic memory management for restarts

ReleaseNotes.md

@@ -271,6 +271,8 @@ For release specific notes visit the [ClusterCockpit Documentation](https://clus
 
 ## Known issues
 
+- The new dynamic memory management is not bullet proof yet across restarts. We
+  will fix that in a subsequent patch release
 - Currently energy footprint metrics of type energy are ignored for calculating
   total energy.
 - With energy footprint metrics of type power the unit is ignored and it is

cmd/cc-backend/main.go

@@ -395,6 +395,7 @@ func runServer(ctx context.Context) error {
 
 	// Set GC percent if not configured
 	if os.Getenv(envGOGC) == "" {
+		// trigger GC when heap grows 15% above the previous live set
 		debug.SetGCPercent(15)
 	}
 	runtime.SystemdNotify(true, "running")