hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Jonathan Gray (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HBASE-3483) No soft flush trigger on global memstore limit
Date Tue, 01 Feb 2011 01:12:29 GMT

    [ https://issues.apache.org/jira/browse/HBASE-3483?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12988984#comment-12988984

Jonathan Gray commented on HBASE-3483:

This is a pretty ugly bug, I say branch and trunk.

> No soft flush trigger on global memstore limit
> ----------------------------------------------
>                 Key: HBASE-3483
>                 URL: https://issues.apache.org/jira/browse/HBASE-3483
>             Project: HBase
>          Issue Type: Bug
>          Components: performance, regionserver
>    Affects Versions: 0.90.0
>            Reporter: Todd Lipcon
>            Assignee: Todd Lipcon
>            Priority: Critical
>             Fix For: 0.90.1
>         Attachments: hbase-3483.txt, hbase-3483.txt
> I think this is the reason people see long blocking periods under write load.
> Currently when we hit the global memstore limit, we call reclaimMemStoreMemory() which
is synchronized - thus everyone has to wait until the memory has flushed down to the low water
mark. This causes every writer to block for 10-15 seconds on a large heap.
> Instead we should start triggering flushes (in another thread) whenever we're above the
low water mark. Then only block writers when we're above the high water mark.

This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira


View raw message