Making metrics faster

glue/main.go

@@ -102,24 +102,27 @@ func (p *Processor) waitForApp() error {
 }
 
 // List returns list of apps
-func (p *Processor) List() (apps.Apps, error) {
+// noUpdate skips stats gathering to speed things up
+func (p *Processor) List(noUpdate bool) (apps.Apps, error) {
 	appList := apps.Apps{}
 
-	statsProcessor := StatsProcessor{
-		DB:         p.DB,
-		DockerSock: p.DockerSock,
-		BindIPHTTP: p.BindIPHTTP,
-		BindIPSSH:  p.BindIPSSH,
-		AppsPath:   p.AppsPath,
-	}
+	if !noUpdate {
+		statsProcessor := StatsProcessor{
+			DB:         p.DB,
+			DockerSock: p.DockerSock,
+			BindIPHTTP: p.BindIPHTTP,
+			BindIPSSH:  p.BindIPSSH,
+			AppsPath:   p.AppsPath,
+		}
 
-	err := statsProcessor.GatherStates()
-	if err != nil {
-		return appList, fmt.Errorf("backend error: %v", err)
+		err := statsProcessor.GatherStates()
+		if err != nil {
+			return appList, fmt.Errorf("backend error: %v", err)
+		}
 	}
 
 	processor := p.getAppProcessor()
-	appList, err = processor.List()
+	appList, err := processor.List()
 
 	if err != nil {
 		return appList, fmt.Errorf("backend error: %v", err)

handlers.go

@@ -29,7 +29,7 @@ func listAppsHandler(c echo.Context) error {
 		AppsPath:   config.AppsPath,
 	}
 
-	applications, err := processor.List()
+	applications, err := processor.List(false)
 	if err != nil {
 		return c.JSONPretty(http.StatusInternalServerError, Message{Message: err.Error()}, JSONIndent)
 	}
@@ -430,7 +430,7 @@ func metricsHandler(c echo.Context) error {
 	metrics += fmt.Sprintf("rosti_node_memory_index{hostname=\"%s\"} %f\n", hostname, node.MemoryIndex)
 	metrics += fmt.Sprintf("rosti_node_sold_memory{hostname=\"%s\"} %d\n", hostname, node.SoldMemory)
 
-	apps, err := processor.List()
+	apps, err := processor.List(true)
 	if err != nil {
 		return c.JSONPretty(http.StatusInternalServerError, Message{Message: err.Error()}, JSONIndent)
 	}

handlers_nats.go

@@ -101,7 +101,7 @@ func listEventHandler(m *nats.Msg, message *RequestMessage) error {
 		AppsPath:   config.AppsPath,
 	}
 
-	applications, err := processor.List()
+	applications, err := processor.List(false)
 	if err != nil {
 		return errorReplyFormater(m, "backend error", err)
 	}