HADOOP-9203. RPCCallBenchmark should find a random available port. Contributec by Andrew Purtell.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1433220 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -540,6 +540,9 @@ Release 2.0.3-alpha - Unreleased
 
     HADOOP-9183. Potential deadlock in ActiveStandbyElector. (tomwhite)
 
+    HADOOP-9203. RPCCallBenchmark should find a random available port.
+    (Andrew Purtell via suresh)
+
 Release 2.0.2-alpha - 2012-09-07 
 
   INCOMPATIBLE CHANGES

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/net/NetUtils.java

@@ -25,6 +25,7 @@
 import java.net.InetSocketAddress;
 import java.net.NetworkInterface;
 import java.net.NoRouteToHostException;
+import java.net.ServerSocket;
 import java.net.Socket;
 import java.net.SocketAddress;
 import java.net.SocketException;
@@ -865,4 +866,23 @@ public static List<InetAddress> getIPs(String subnet,
     }
     return addrs;
   }
+
+  /**
+   * Return a free port number. There is no guarantee it will remain free, so
+   * it should be used immediately.
+   *
+   * @returns A free port for binding a local socket
+   */
+  public static int getFreeSocketPort() {
+    int port = 0;
+    try {
+      ServerSocket s = new ServerSocket(0);
+      port = s.getLocalPort();
+      s.close();
+      return port;
+    } catch (IOException e) {
+      // Could not get a free port. Return default port 0.
+    }
+    return port;
+  }
 }

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/ipc/RPCCallBenchmark.java

@@ -67,7 +67,7 @@ private static class MyOptions {
     private int serverReaderThreads = 1;
     private int clientThreads = 0;
     private String host = "0.0.0.0";
-    private int port = 12345;
+    private int port = 0;
     public int secondsToRun = 15;
     private int msgSize = 1024;
     public Class<? extends RpcEngine> rpcEngine =
@@ -201,11 +201,21 @@ private void processOptions(CommandLine line, Options opts)
       }
     }
     
+    public int getPort() {
+      if (port == 0) {
+        port = NetUtils.getFreeSocketPort();
+        if (port == 0) {
+          throw new RuntimeException("Could not find a free port");
+        }
+      }
+      return port;
+    }
+
     @Override
     public String toString() {
       return "rpcEngine=" + rpcEngine + "\nserverThreads=" + serverThreads
           + "\nserverReaderThreads=" + serverReaderThreads + "\nclientThreads="
-          + clientThreads + "\nhost=" + host + "\nport=" + port
+          + clientThreads + "\nhost=" + host + "\nport=" + getPort()
           + "\nsecondsToRun=" + secondsToRun + "\nmsgSize=" + msgSize;
     }
   }
@@ -228,12 +238,12 @@ private Server startServer(MyOptions opts) throws IOException {
           .newReflectiveBlockingService(serverImpl);
 
       server = new RPC.Builder(conf).setProtocol(TestRpcService.class)
-          .setInstance(service).setBindAddress(opts.host).setPort(opts.port)
+          .setInstance(service).setBindAddress(opts.host).setPort(opts.getPort())
           .setNumHandlers(opts.serverThreads).setVerbose(false).build();
     } else if (opts.rpcEngine == WritableRpcEngine.class) {
       server = new RPC.Builder(conf).setProtocol(TestProtocol.class)
           .setInstance(new TestRPC.TestImpl()).setBindAddress(opts.host)
-          .setPort(opts.port).setNumHandlers(opts.serverThreads)
+          .setPort(opts.getPort()).setNumHandlers(opts.serverThreads)
           .setVerbose(false).build();
     } else {
       throw new RuntimeException("Bad engine: " + opts.rpcEngine);
@@ -378,7 +388,7 @@ private interface RpcServiceWrapper {
    * Create a client proxy for the specified engine.
    */
   private RpcServiceWrapper createRpcClient(MyOptions opts) throws IOException {
-    InetSocketAddress addr = NetUtils.createSocketAddr(opts.host, opts.port);
+    InetSocketAddress addr = NetUtils.createSocketAddr(opts.host, opts.getPort());
     
     if (opts.rpcEngine == ProtobufRpcEngine.class) {
       final TestRpcService proxy = RPC.getProxy(TestRpcService.class, 0, addr, conf);