You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@oozie.apache.org by "Roman Shaposhnik (JIRA)" <ji...@apache.org> on 2011/09/10 06:07:10 UTC
[jira] [Reopened] (OOZIE-348) GH-561: Redesign oozie internal queue
[ https://issues.apache.org/jira/browse/OOZIE-348?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Roman Shaposhnik reopened OOZIE-348:
------------------------------------
> GH-561: Redesign oozie internal queue
> -------------------------------------
>
> Key: OOZIE-348
> URL: https://issues.apache.org/jira/browse/OOZIE-348
> Project: Oozie
> Issue Type: Bug
> Reporter: Hadoop QA
>
> We had a lot of issues related to oozie internal queue. It includes queue overflow as well as re-queuing the same overly used commands to avoid starvation. There are other situations too. This problem becomes very obvious in very high-load case.
> I would like to open-up the discussion to find out a better architectural design for longer term considering a very high-load situation.
> The following proposals are to initiate the discussion that varied from complete overhaul to adjusting the current design:
> 1. Implement the queue idea into DB:
> Pros: Persistence. In hot-hot or load balancing situation it useful. Single place of truth. Different level of ordering could be done as needed through SQL. Don't bother about queue size. Don't need to recreate in every restart -- recovery service might be less busy.
> Cons: Extra DB access overhead.
> Middle approach could be to keep a memory cache with strict conditions. The details could be discussed later.
> 2. Re-queuing the same commands (that is used for throttling) -- should be redesigned. In this case, make sure queuing happens in the *same* place -- not at the end of queue. I know this will break the queue meaning. In this case, we might need to use a different data structure.
> Currently queuing the same command at the end created starvation ( live-lock) like situation.
> 3. Multiple queues. One for coordinator input check that is used 99% of time.
> Comments?
> Regards,
> Mohammad
--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira