From 0431f2430df3d38f4a4000e79cdcb57db3cebec7 Mon Sep 17 00:00:00 2001
From: Daniel Smith <dbsmith@google.com>
Date: Mon, 13 Oct 2014 14:46:31 -0700
Subject: [PATCH] Use cache for minion lookups, don't hammer apiserver

---
 cmd/integration/integration.go          |  5 +----
 plugin/cmd/scheduler/scheduler.go       |  5 +----
 plugin/pkg/scheduler/factory/factory.go | 18 ++++++++++++++----
 3 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/cmd/integration/integration.go b/cmd/integration/integration.go
index d71f53d3c00..5ddafc3cdee 100644
--- a/cmd/integration/integration.go
+++ b/cmd/integration/integration.go
@@ -137,10 +137,7 @@ func startComponents(manifestURL string) (apiServerURL string) {
 
 	// Scheduler
 	schedulerConfigFactory := &factory.ConfigFactory{cl}
-	schedulerConfig, err := schedulerConfigFactory.Create()
-	if err != nil {
-		glog.Fatalf("Unable to construct scheduler config: %v", err)
-	}
+	schedulerConfig := schedulerConfigFactory.Create()
 	scheduler.New(schedulerConfig).Run()
 
 	endpoints := service.NewEndpointController(cl)
diff --git a/plugin/cmd/scheduler/scheduler.go b/plugin/cmd/scheduler/scheduler.go
index 93850e59c96..ca872ef0437 100644
--- a/plugin/cmd/scheduler/scheduler.go
+++ b/plugin/cmd/scheduler/scheduler.go
@@ -58,10 +58,7 @@ func main() {
 	go http.ListenAndServe(net.JoinHostPort(address.String(), strconv.Itoa(*port)), nil)
 
 	configFactory := &factory.ConfigFactory{Client: kubeClient}
-	config, err := configFactory.Create()
-	if err != nil {
-		glog.Fatalf("Can't create scheduler config: %v", err)
-	}
+	config := configFactory.Create()
 	s := scheduler.New(config)
 	s.Run()
 
diff --git a/plugin/pkg/scheduler/factory/factory.go b/plugin/pkg/scheduler/factory/factory.go
index 9b5e72076ec..91948c6c785 100644
--- a/plugin/pkg/scheduler/factory/factory.go
+++ b/plugin/pkg/scheduler/factory/factory.go
@@ -19,6 +19,7 @@ limitations under the License.
 package factory
 
 import (
+	"fmt"
 	"math/rand"
 	"sync"
 	"time"
@@ -42,7 +43,7 @@ type ConfigFactory struct {
 }
 
 // Create creates a scheduler and all support functions.
-func (factory *ConfigFactory) Create() (*scheduler.Config, error) {
+func (factory *ConfigFactory) Create() *scheduler.Config {
 	// Watch and queue pods that need scheduling.
 	podQueue := cache.NewFIFO()
 	cache.NewReflector(factory.createUnassignedPodLW(), &api.Pod{}, podQueue).Run()
@@ -63,13 +64,14 @@ func (factory *ConfigFactory) Create() (*scheduler.Config, error) {
 	}
 
 	r := rand.New(rand.NewSource(time.Now().UnixNano()))
+	minionLister := &storeToMinionLister{minionCache}
 
 	algo := algorithm.NewGenericScheduler(
 		[]algorithm.FitPredicate{
 			// Fit is defined based on the absence of port conflicts.
 			algorithm.PodFitsPorts,
 			// Fit is determined by resource availability
-			algorithm.NewResourceFitPredicate(algorithm.ClientNodeInfo{factory.Client}),
+			algorithm.NewResourceFitPredicate(minionLister),
 		},
 		// Prioritize nodes by least requested utilization.
 		algorithm.LeastRequestedPriority,
@@ -81,7 +83,7 @@ func (factory *ConfigFactory) Create() (*scheduler.Config, error) {
 	}
 
 	return &scheduler.Config{
-		MinionLister: &storeToMinionLister{minionCache},
+		MinionLister: minionLister,
 		Algorithm:    algo,
 		Binder:       &binder{factory.Client},
 		NextPod: func() *api.Pod {
@@ -93,7 +95,7 @@ func (factory *ConfigFactory) Create() (*scheduler.Config, error) {
 			return pod
 		},
 		Error: factory.makeDefaultErrorFunc(&podBackoff, podQueue),
-	}, nil
+	}
 }
 
 type listWatch struct {
@@ -204,6 +206,14 @@ func (s *storeToMinionLister) List() (machines api.MinionList, err error) {
 	return machines, nil
 }
 
+// GetNodeInfo returns cached data for the minion 'id'.
+func (s *storeToMinionLister) GetNodeInfo(id string) (*api.Minion, error) {
+	if minion, ok := s.Get(id); ok {
+		return minion.(*api.Minion), nil
+	}
+	return nil, fmt.Errorf("minion '%v' is not in cache")
+}
+
 // storeToPodLister turns a store into a pod lister. The store must contain (only) pods.
 type storeToPodLister struct {
 	cache.Store