Bug: Is there any risks that more than one `NewPodTopologyCache` running in one Scheduler App?

[NoicFank]

Func NewPodTopologyCache responses to build a common cache for plugin NodeResourceTopologyMatch, and it will be called in plugin's New func as following:

func New(args runtime.Object, handle framework.Handle) (framework.Plugin, error) {
	...
	topologyMatch := &TopologyMatch{
                // here initializing the cache
		PodTopologyCache:       NewPodTopologyCache(ctx, 30*time.Minute),
		handle:                 handle,
		lister:                 lister,
		topologyAwareResources: sets.NewString(cfg.TopologyAwareResources...),
	}

	return topologyMatch, nil
}

Then, once plugin NodeResourceTopologyMatch appears in multi profiles for one scheduler app, then the plugin will be initialized many times, which means the upper func New will be triggered more than once.

Then, the most important thing is multi PodTopologyCache shows in one scheduler app. Is there any potential risks in this situation(e.g. data race)?

@Garrybest @qmhu PTAL, thanks

[NoicFank]

The nearly same thing is putting the creating SharedInformerFactory into plugin as following, Then there will be many informers for same one Resource(GVK), which means there will be many duplicate same indexer(local cache) for one Resource.

And for this case, not only 「same plugin appears in multi profiles」 will trigger this, once resource is used in other plugins will also trigger this.

It could bring many memory pressure when all the same informers to list same one resource, which may trigger OOM.

And there is chance that indexer inconsistency for one resource

func initTopologyInformer(
	ctx context.Context,
	client topologyclientset.Interface,
) (listerv1alpha1.NodeResourceTopologyLister, error) {
	topologyInformerFactory := informers.NewSharedInformerFactory(client, 0)
	nrtLister := topologyInformerFactory.Topology().V1alpha1().NodeResourceTopologies().Lister()

	klog.V(4).InfoS("Start nodeTopologyInformer")
	topologyInformerFactory.Start(ctx.Done())
	topologyInformerFactory.WaitForCacheSync(ctx.Done())
	return nrtLister, nil
}

[NoicFank]

In my opinion, Bring initialization of SharedInformerFactory and Self-Define Cache into cmd.main, which means plugin's func New() should be wrapped that SharedInformerFactory and Self-Define Cache will be injected into plugin as plugin.New() parameters.

[qmhu]

Which situation will create more than one noderesourcetopology plugin?