Merge pull request #4461 from kubernetes-client/copilot/fix-websocket-flush-delay

Reduce WebSocket flush wait from 100ms to 1ms

Author: k8s-ci-robot

util/src/main/java/io/kubernetes/client/util/WebSocketStreamHandler.java

@@ -244,6 +244,10 @@ private class WebSocketOutputStream extends OutputStream {
 
     private static final int WAIT_MILLIS = 10;
 
+    private static final int FLUSH_WAIT_MILLIS = 1;
+
+    private static final int MAX_FLUSH_ITERATIONS = MAX_WAIT_MILLIS / FLUSH_WAIT_MILLIS;
+
     private final byte stream;
 
     public WebSocketOutputStream(int stream) {
@@ -272,11 +276,11 @@ public void flush() throws IOException {
       int i = 0;
       while (WebSocketStreamHandler.this.socket.queueSize() > 0) {
         try {
-          Thread.sleep(100);
+          Thread.sleep(FLUSH_WAIT_MILLIS);
         } catch (InterruptedException ex) {
         }
         // Wait a maximum of 10 seconds.
-        if (i++ > 100) {
+        if (i++ > MAX_FLUSH_ITERATIONS) {
           throw new IOException("Timed out waiting for web-socket to flush.");
         }
       }