[jira] [Commented] (YARN-1069) Deterministic MiniYARNCluster

["Maysam Yabandeh (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/YARN-1069?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13742003#comment-13742003 ] 

Maysam Yabandeh commented on YARN-1069:
---------------------------------------

One example I have in mind is sending NM update events to RM in NodeStatusUpdaterImpl#startStatusUpdater, where the heartbeat is sent periodically:
{code:java}
   statusUpdaterRunnable = new Runnable() {
      @Override
      @SuppressWarnings("unchecked")
      public void run() {
        int lastHeartBeatID = 0;
        while (!isStopped) {
          // Send heartbeat
{code}

We can simply wrap the functionality in a separate method and call the method inside the timer. The tester can then configure the MiniYarnCluster to directly call the exposed method instead of running the timer.
                
> Deterministic MiniYARNCluster
> -----------------------------
>
>                 Key: YARN-1069
>                 URL: https://issues.apache.org/jira/browse/YARN-1069
>             Project: Hadoop YARN
>          Issue Type: Test
>    Affects Versions: 2.1.0-beta
>            Reporter: Maysam Yabandeh
>            Assignee: Maysam Yabandeh
>            Priority: Minor
>
> Currently the order of events in MiniYarnCluster is nondeterministic as the events are triggered by scheduled timers. This makes it difficult to write tests since some erroneous scenarios are triggered only after some particular sequence of events. An example is the bug in YARN-779 where without this control over events, writing a deterministic unit test is not possible. We should modify the source to allow both manual invocation of events as well as via existing periodic timers. MiniYarnCluster can then expose such methods for more control over events ordering.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira