HADOOP-1849. Add undocumented configuration parameter for per handler call queue size in IPC Server. Contributed by Konstantin Shvachko.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@916529 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -1392,14 +1392,6 @@ Release 0.20.2 - 2010-2-16
     HADOOP-6218. Adds a feature where TFile can be split by Record
     Sequence number. (Hong Tang and Raghu Angadi via ddas)
 
-  IMPROVEMENTS
-
-    HADOOP-5611. Fix C++ libraries to build on Debian Lenny. (Todd Lipcon
-    via tomwhite)
-
-    HADOOP-5612. Some c++ scripts are not chmodded before ant execution.
-    (Todd Lipcon via tomwhite)
-
   BUG FIXES
 
     HADOOP-6231. Allow caching of filesystem instances to be disabled on a
@@ -1424,6 +1416,17 @@ Release 0.20.2 - 2010-2-16
     HADOOP-6498. IPC client bug may cause rpc call hang. (Ruyue Ma and
     hairong via hairong)
 
+  IMPROVEMENTS
+
+    HADOOP-5611. Fix C++ libraries to build on Debian Lenny. (Todd Lipcon
+    via tomwhite)
+
+    HADOOP-5612. Some c++ scripts are not chmodded before ant execution.
+    (Todd Lipcon via tomwhite)
+
+    HADOOP-1849. Add undocumented configuration parameter for per handler 
+    call queue size in IPC Server. (shv)
+
 Release 0.20.1 - 2009-09-01
 
   INCOMPATIBLE CHANGES

src/java/org/apache/hadoop/fs/CommonConfigurationKeys.java

@@ -123,6 +123,15 @@ public class CommonConfigurationKeys {
                                        "ipc.server.max.response.size";
   public static final int     IPC_SERVER_RPC_MAX_RESPONSE_SIZE_DEFAULT = 
                                         1024*1024;
+  /**
+   * How many calls per handler are allowed in the queue.
+   */
+  public static final String  IPC_SERVER_HANDLER_QUEUE_SIZE_KEY = 
+                                       "ipc.server.handler.queue.size";
+  /**
+   * The default number of calls per handler in the queue.
+   */
+  public static final int IPC_SERVER_HANDLER_QUEUE_SIZE_DEFAULT = 100;
 
   public static final String  HADOOP_RPC_SOCKET_FACTORY_CLASS_DEFAULT_KEY = 
                                        "hadoop.rpc.socket.factory.class.default";

src/java/org/apache/hadoop/ipc/Server.java

@@ -60,8 +60,6 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.CommonConfigurationKeys;
-
-import static org.apache.hadoop.fs.CommonConfigurationKeys.*;
 import org.apache.hadoop.io.Writable;
 import org.apache.hadoop.io.WritableUtils;
 import org.apache.hadoop.ipc.metrics.RpcMetrics;
@@ -98,12 +96,7 @@ public abstract class Server {
   // 3 : Introduce the protocol into the RPC connection header
   // 4 : Introduced SASL security layer
   public static final byte CURRENT_VERSION = 4;
-  
-  /**
-   * How many calls/handler are allowed in the queue.
-   */
-  private static final int MAX_QUEUE_SIZE_PER_HANDLER = 100;
-  
+
   /**
    * Initial and max size of response buffer
    */
@@ -1288,9 +1281,12 @@ public abstract class Server {
     this.paramClass = paramClass;
     this.handlerCount = handlerCount;
     this.socketSendBufferSize = 0;
-    this.maxQueueSize = handlerCount * MAX_QUEUE_SIZE_PER_HANDLER;
-    this.maxRespSize = conf.getInt(IPC_SERVER_RPC_MAX_RESPONSE_SIZE_KEY,
-                                   IPC_SERVER_RPC_MAX_RESPONSE_SIZE_DEFAULT);
+    this.maxQueueSize = handlerCount * conf.getInt(
+        CommonConfigurationKeys.IPC_SERVER_HANDLER_QUEUE_SIZE_KEY,
+        CommonConfigurationKeys.IPC_SERVER_HANDLER_QUEUE_SIZE_DEFAULT);
+    this.maxRespSize = conf.getInt(
+        CommonConfigurationKeys.IPC_SERVER_RPC_MAX_RESPONSE_SIZE_KEY,
+        CommonConfigurationKeys.IPC_SERVER_RPC_MAX_RESPONSE_SIZE_DEFAULT);
     this.callQueue  = new LinkedBlockingQueue<Call>(maxQueueSize); 
     this.maxIdleTime = 2*conf.getInt("ipc.client.connection.maxidletime", 1000);
     this.maxConnectionsToNuke = conf.getInt("ipc.client.kill.max", 10);