Use a minimum of 3 dispatcher threads to avoid deadlocks

apache · May 27, 2016 · 139e875 · 139e875
1 parent d5911d1
commit 139e875
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/core/src/main/scala/org/apache/spark/rpc/netty/Dispatcher.scala b/core/src/main/scala/org/apache/spark/rpc/netty/Dispatcher.scala
@@ -192,8 +192,9 @@ private[netty] class Dispatcher(nettyEnv: NettyRpcEnv) extends Logging {
 
   /** Thread pool used for dispatching messages. */
   private val threadpool: ThreadPoolExecutor = {
+    // Use a minimum of 3 threads to avoid deadlocks
     val numThreads = nettyEnv.conf.getInt("spark.rpc.netty.dispatcher.numThreads",
-      math.max(2, Runtime.getRuntime.availableProcessors()))
+      math.max(3, Runtime.getRuntime.availableProcessors()))
     val pool = ThreadUtils.newDaemonFixedThreadPool(numThreads, "dispatcher-event-loop")
     for (i <- 0 until numThreads) {
       pool.execute(new MessageLoop)