Merge pull request kubernetes-csi#286 from RaunakShah/throughput

Add configurable throughput parameters for clients to API server

README.md

@@ -74,6 +74,10 @@ Note that the external-attacher does not scale with more replicas. Only one exte
 
 * `--reconcile-sync`: Resync frequency of the attached volumes with the driver. See [Periodic re-sync](#periodic-re-sync) for details. 1 minute is used by default.
 
+* `--kube-api-qps`: The number of requests per second sent by a Kubernetes client to the Kubernetes API server. Defaults to `5.0`.
+
+* `--kube-api-burst`: The number of requests to the Kubernetes API server, exceeding the QPS, that can be sent at any given time. Defaults to `10`.
+
 #### Other recognized arguments
 
 * `--kubeconfig <path>`: Path to Kubernetes client configuration that the external-attacher uses to connect to Kubernetes API server. When omitted, default token provided by Kubernetes will be used. This option is useful only when the external-attacher does not run as a Kubernetes pod, e.g. for debugging.

cmd/csi-attacher/main.go

@@ -70,6 +70,9 @@ var (
 	metricsAddress = flag.String("metrics-address", "", "(deprecated) The TCP network address where the prometheus metrics endpoint will listen (example: `:8080`). The default is empty string, which means metrics endpoint is disabled. Only one of `--metrics-address` and `--http-endpoint` can be set.")
 	httpEndpoint   = flag.String("http-endpoint", "", "The TCP network address where the HTTP server for diagnostics, including metrics and leader election health check, will listen (example: `:8080`). The default is empty string, which means the server is disabled. Only one of `--metrics-address` and `--http-endpoint` can be set.")
 	metricsPath    = flag.String("metrics-path", "/metrics", "The HTTP path where prometheus metrics will be exposed. Default is `/metrics`.")
+
+	kubeAPIQPS   = flag.Float64("kube-api-qps", 5, "QPS to use while communicating with the kubernetes apiserver. Defaults to 5.0.")
+	kubeAPIBurst = flag.Int("kube-api-burst", 10, "Burst to use while communicating with the kubernetes apiserver. Defaults to 10.")
 )
 
 var (
@@ -107,6 +110,8 @@ func main() {
 		klog.Error(err.Error())
 		os.Exit(1)
 	}
+	config.QPS = (float32)(*kubeAPIQPS)
+	config.Burst = *kubeAPIBurst
 
 	if *workerThreads == 0 {
 		klog.Error("option -worker-threads must be greater than zero")