Update for the new interface.

cmd/metrics-example/metrics-example.go

@@ -111,13 +111,7 @@ func main() {
 	}
 
 	metrics.RegisterRuntimeMemStats(r)
-	go func() {
-		t := time.NewTicker(5e9)
-		for {
-			<-t.C
-			metrics.CaptureRuntimeMemStats(r, true)
-		}
-	}()
+	metrics.CaptureRuntimeMemStats(r, 5)
 
 	metrics.Log(r, 60, log.New(os.Stderr, "metrics: ", log.Lmicroseconds))