cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Sylvain Lebresne (Commented) (JIRA)" <>
Subject [jira] [Commented] (CASSANDRA-3484) Bizarre Compaction Manager Behaviour
Date Fri, 11 Nov 2011 19:48:53 GMT


Sylvain Lebresne commented on CASSANDRA-3484:

We can commit either this patch or the one on CASSANDRA-2407 for this issue (since they both
fix the issue here). But the goal of #2407 is a bit different so we just should leave that
issue solve the problem it want to solve.
> Bizarre Compaction Manager Behaviour
> ------------------------------------
>                 Key: CASSANDRA-3484
>                 URL:
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.0.2
>         Environment: RHEL 6
> java version "1.6.0_26"
> 6 node cluster (5 nodes 0.8.6, 1 node 1.0.2 minus CASSANDRA-2503)
>            Reporter: Dan Hendry
>         Attachments: 3484.txt, compaction.png
> It seems the CompactionManager has gotten itself into a bad state. My 1.0.2 node has
been up for 20 hours now - checking via JMX, the compaction manager is reporting that it has
completed 14,797,412,000 tasks. Yep, thats right 14 billion tasks and increasing at a rate
of roughly 208,400/second. 
> I should point out that I am currently running a major compaction on the node. My theory
is that this problem was introduced by CASSANDRA-3363. It looks like SizeTieredCompactionStrategy.getBackgroundTasks()
returns a set of task without consideration for any in-progress compactions. Compactions are
only kicked off if task.markSSTablesForCompaction() returns true (CompactionManager line 127)
but the task resubmission is based only on the task list not being empty (CompactionManager
line 141). Should the logic not be to only reschedule if a task has actually been executed?
> I am just waiting now for the major compaction to finish to see if the problem goes away
as would be suggested by my theory.

This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:!default.jspa
For more information on JIRA, see:


View raw message