Author: llu Date: Tue Jul 24 22:52:22 2012 New Revision: 1365331 URL: http://svn.apache.org/viewvc?rev=1365331&view=rev Log: MAPREDUCE-4400: Fix performance regression for small jobs/workflows
Modified: hadoop/common/branches/branch-1/CHANGES.txt hadoop/common/branches/branch-1/src/mapred/org/apache/hadoop/mapred/Task.java Modified: hadoop/common/branches/branch-1/CHANGES.txt URL: http://svn.apache.org/viewvc/hadoop/common/branches/branch-1/CHANGES.txt?rev=1365331&r1=1365330&r2=1365331&view=diff ============================================================================== --- hadoop/common/branches/branch-1/CHANGES.txt (original) +++ hadoop/common/branches/branch-1/CHANGES.txt Tue Jul 24 22:52:22 2012 @@ -242,6 +242,9 @@ Release 1.1.0 - unreleased MAPREDUCE-4399. Change the Jetty response buffer size to improve shuffle performance. (Luke Lu via suresh) + MAPREDUCE-4400. Avoid task finish sleep to improve small job/workflow + latency. (llu) + BUG FIXES MAPREDUCE-4087. [Gridmix] GenerateDistCacheData job of Gridmix can Modified: hadoop/common/branches/branch-1/src/mapred/org/apache/hadoop/mapred/Task.java URL: http://svn.apache.org/viewvc/hadoop/common/branches/branch-1/src/mapred/org/apache/hadoop/mapred/Task.java?rev=1365331&r1=1365330&r2=1365331&view=diff ============================================================================== --- hadoop/common/branches/branch-1/src/mapred/org/apache/hadoop/mapred/Task.java (original) +++ hadoop/common/branches/branch-1/src/mapred/org/apache/hadoop/mapred/Task.java Tue Jul 24 22:52:22 2012 @@ -649,14 +649,19 @@ abstract public class Task implements Wr // get current flag value and reset it as well boolean sendProgress = resetProgressFlag(); while (!taskDone.get()) { - synchronized(lock) { - done = false; - } try { boolean taskFound = true; // whether TT knows about this task // sleep for a bit try { - Thread.sleep(PROGRESS_INTERVAL); + synchronized(lock) { + done = false; + lock.wait(PROGRESS_INTERVAL); + if (taskDone.get()) { + done = true; + lock.notify(); + return; + } + } } catch (InterruptedException e) { if (LOG.isDebugEnabled()) { @@ -724,6 +729,7 @@ abstract public class Task implements Wr // Updating resources specified in ResourceCalculatorPlugin if (pingThread != null) { synchronized(lock) { + lock.notify(); // wake up the wait in the while loop while(!done) { lock.wait(); }