Merge pull request #23 from newrelic/gsanchez/fix/cache

Improve performance of cache Put func

cfclient/cfapps/cache.go

@@ -12,15 +12,17 @@ import (
 
 // Cache ...
 type Cache struct {
-	Collection map[string]*CFApp
-	sync       *sync.RWMutex
+	Collection  map[string]*CFApp
+	WriteBuffer chan *CFApp
+	sync        *sync.RWMutex
 }
 
 // NewCache ...
 func NewCache() *Cache {
 	cache := &Cache{
-		Collection: map[string]*CFApp{},
-		sync:       &sync.RWMutex{},
+		Collection:  map[string]*CFApp{},
+		WriteBuffer: make(chan *CFApp, 1024),
+		sync:        &sync.RWMutex{},
 	}
 	cache.Start()
 	return cache
@@ -57,6 +59,11 @@ func (c *Cache) Start() {
 					v.UpdateInstances()
 				}
 				c.sync.RUnlock()
+
+			case app := <-c.WriteBuffer:
+				c.sync.Lock()
+				c.Collection[app.GUID] = app
+				c.sync.Unlock()
 			}
 		}
 	}()
@@ -74,17 +81,6 @@ func (c *Cache) Get(id string) (app *CFApp, found bool) {
 }
 
 // Put ...
-func (c *Cache) Put(id string) *CFApp {
-	c.sync.Lock()
-	defer c.sync.Unlock()
-
-	if app, found := c.Collection[id]; found {
-		return app
-	}
-	GetInstance().app.Log.Debug("Adding new app: ", id)
-	app := NewCFApp(id)
-	c.Collection[app.GUID] = app
-	GetInstance().UpdateAppAsync(app)
-
-	return app
+func (c *Cache) Put(app *CFApp) {
+	c.WriteBuffer <- app
 }

cfclient/cfapps/manager.go

@@ -63,22 +63,27 @@ func (c *CFAppManager) GetAppInstanceAttributes(appID string, instanceID int32)
 }
 
 // GetApp ...
-func (c *CFAppManager) GetApp(guid string) *CFApp {
-	if app, found := c.Cache.Get(guid); found {
+func (c *CFAppManager) GetApp(guid string) (app *CFApp) {
+	var found bool
+	if app, found = c.Cache.Get(guid); found {
 		return app
 	}
-	return c.Cache.Put(guid)
+	app = NewCFApp(guid)
+	c.app.Log.Debug("Adding new app: ", guid)
+	c.Cache.Put(app)
+	c.updateAppAsync(app)
+	return app
 }
 
-func (c *CFAppManager) UpdateAppAsync(app *CFApp) {
+func (c *CFAppManager) updateAppAsync(app *CFApp) {
 	go func() {
 		if err := c.FetchApp(app); err != nil {
 			if atomic.LoadInt32(&app.retryCount) > 2 {
 				c.app.Log.Warn("Max retries trying to fetch app: ", app.GUID)
 				return
 			}
 			atomic.AddInt32(&app.retryCount, 1)
-			c.UpdateAppAsync(app)
+			c.updateAppAsync(app)
 		} else {
 			atomic.StoreInt32(&app.retryCount, 0)
 		}