Merge pull request #18015 from wojtek-t/list_traces

Auto commit by PR queue bot

pkg/apiserver/resthandler.go

@@ -219,6 +219,9 @@ func (r *responder) Error(err error) {
 // ListResource returns a function that handles retrieving a list of resources from a rest.Storage object.
 func ListResource(r rest.Lister, rw rest.Watcher, scope RequestScope, forceWatch bool, minRequestTimeout time.Duration) restful.RouteFunction {
 	return func(req *restful.Request, res *restful.Response) {
+		// For performance tracking purposes.
+		trace := util.NewTrace("List " + req.Request.URL.Path)
+
 		w := res.ResponseWriter
 
 		namespace, err := scope.Namer.Namespace(req)
@@ -297,16 +300,23 @@ func ListResource(r rest.Lister, rw rest.Watcher, scope RequestScope, forceWatch
 			return
 		}
 
+		// Log only long List requests (ignore Watch).
+		defer trace.LogIfLong(500 * time.Millisecond)
+		trace.Step("About to List from storage")
 		result, err := r.List(ctx, &opts)
 		if err != nil {
 			errorJSON(err, scope.Codec, w)
 			return
 		}
-		if err := setListSelfLink(result, req, scope.Namer); err != nil {
+		trace.Step("Listing from storage done")
+		numberOfItems, err := setListSelfLink(result, req, scope.Namer)
+		if err != nil {
 			errorJSON(err, scope.Codec, w)
 			return
 		}
+		trace.Step("Self-linking done")
 		write(http.StatusOK, scope.Kind.GroupVersion(), scope.Codec, result, w, req.Request)
+		trace.Step(fmt.Sprintf("Writing http response done (%d items)", numberOfItems))
 	}
 }
 
@@ -784,16 +794,16 @@ func checkName(obj runtime.Object, name, namespace string, namer ScopeNamer) err
 }
 
 // setListSelfLink sets the self link of a list to the base URL, then sets the self links
-// on all child objects returned.
-func setListSelfLink(obj runtime.Object, req *restful.Request, namer ScopeNamer) error {
+// on all child objects returned. Returns the number of items in the list.
+func setListSelfLink(obj runtime.Object, req *restful.Request, namer ScopeNamer) (int, error) {
 	if !meta.IsListType(obj) {
-		return nil
+		return 0, nil
 	}
 
 	// TODO: List SelfLink generation should return a full URL?
 	path, query, err := namer.GenerateListLink(req)
 	if err != nil {
-		return err
+		return 0, err
 	}
 	newURL := *req.Request.URL
 	newURL.Path = path
@@ -807,15 +817,14 @@ func setListSelfLink(obj runtime.Object, req *restful.Request, namer ScopeNamer)
 	// Set self-link of objects in the list.
 	items, err := meta.ExtractList(obj)
 	if err != nil {
-		return err
+		return 0, err
 	}
 	for i := range items {
 		if err := setSelfLink(items[i], req, namer); err != nil {
-			return err
+			return len(items), err
 		}
 	}
-	return meta.SetList(obj, items)
-
+	return len(items), meta.SetList(obj, items)
 }
 
 func getPatchedJS(patchType api.PatchType, originalJS, patchJS []byte, obj runtime.Object) ([]byte, error) {

pkg/registry/generic/etcd/etcd.go

@@ -176,20 +176,15 @@ func (e *Etcd) List(ctx api.Context, options *unversioned.ListOptions) (runtime.
 // ListPredicate returns a list of all the items matching m.
 func (e *Etcd) ListPredicate(ctx api.Context, m generic.Matcher, options *unversioned.ListOptions) (runtime.Object, error) {
 	list := e.NewListFunc()
-	trace := util.NewTrace("List " + reflect.TypeOf(list).String())
 	filterFunc := e.filterAndDecorateFunction(m)
-	defer trace.LogIfLong(600 * time.Millisecond)
 	if name, ok := m.MatchesSingle(); ok {
 		if key, err := e.KeyFunc(ctx, name); err == nil {
-			trace.Step("About to read single object")
 			err := e.Storage.GetToList(ctx, key, filterFunc, list)
-			trace.Step("Object extracted")
 			return list, etcderr.InterpretListError(err, e.EndpointName)
 		}
 		// if we cannot extract a key based on the current context, the optimization is skipped
 	}
 
-	trace.Step("About to list directory")
 	if options == nil {
 		options = &unversioned.ListOptions{ResourceVersion: "0"}
 	}
@@ -198,7 +193,6 @@ func (e *Etcd) ListPredicate(ctx api.Context, m generic.Matcher, options *unvers
 		return nil, err
 	}
 	err = e.Storage.List(ctx, e.KeyRootFunc(ctx), version, filterFunc, list)
-	trace.Step("List extracted")
 	return list, etcderr.InterpretListError(err, e.EndpointName)
 }