diff --git a/java/compiler/impl/src/com/intellij/compiler/server/BuildManager.java b/java/compiler/impl/src/com/intellij/compiler/server/BuildManager.java
index d86be2d6acb1..4a3e60982702 100644
--- a/java/compiler/impl/src/com/intellij/compiler/server/BuildManager.java
+++ b/java/compiler/impl/src/com/intellij/compiler/server/BuildManager.java
@@ -128,7 +128,7 @@ public class BuildManager implements ApplicationComponent{
 
   private final ChannelGroup myAllOpenChannels = new DefaultChannelGroup("build-manager");
   private final BuildMessageDispatcher myMessageDispatcher = new BuildMessageDispatcher();
-  private int myListenPort = -1;
+  private volatile int myListenPort = -1;
   private volatile CmdlineRemoteProto.Message.ControllerMessage.GlobalSettings myGlobals;
 
   public BuildManager(final ProjectManager projectManager) {
@@ -380,7 +380,11 @@ public class BuildManager implements ApplicationComponent{
     // ensure server is listening
     if (myListenPort < 0) {
       try {
-        myListenPort = startListening();
+        synchronized (this) {
+          if (myListenPort < 0) {
+            myListenPort = startListening();
+          }
+        }
       }
       catch (Exception e) {
         handler.handleFailure(sessionId, CmdlineProtoUtil.createFailure(e.getMessage(), null));
@@ -795,7 +799,7 @@ public class BuildManager implements ApplicationComponent{
   }
 
   private int startListening() throws Exception {
-    final ChannelFactory channelFactory = new NioServerSocketChannelFactory(myPooledThreadExecutor, myPooledThreadExecutor);
+    final ChannelFactory channelFactory = new NioServerSocketChannelFactory(myPooledThreadExecutor, myPooledThreadExecutor, Math.min(4, Math.max(2, Runtime.getRuntime().availableProcessors())));
     final SimpleChannelUpstreamHandler channelRegistrar = new SimpleChannelUpstreamHandler() {
       public void channelOpen(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception {
         myAllOpenChannels.add(e.getChannel());