lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Simon Willnauer (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (LUCENE-4462) Publishing flushed segments is single threaded and too costly
Date Mon, 08 Oct 2012 21:34:03 GMT

    [ https://issues.apache.org/jira/browse/LUCENE-4462?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13471882#comment-13471882
] 

Simon Willnauer commented on LUCENE-4462:
-----------------------------------------

bq. I think we should keep the safety in there (the fallback to forcePurge if too many segments
are backlogged)...? Hopefully it never needs to run... but just in case.

I agree, I remove it for beasting. I will add back and commit. I will let this bake in a bit
and then port to 4.x
                
> Publishing flushed segments is single threaded and too costly
> -------------------------------------------------------------
>
>                 Key: LUCENE-4462
>                 URL: https://issues.apache.org/jira/browse/LUCENE-4462
>             Project: Lucene - Core
>          Issue Type: Improvement
>            Reporter: Michael McCandless
>            Assignee: Simon Willnauer
>         Attachments: LUCENE-4462.patch
>
>
> Spinoff from http://lucene.markmail.org/thread/4li6bbomru35qn7w
> The new TestBagOfPostings failed the build because it timed out after 2 hours ... but
in digging I found that it was a starvation issue: the 4 threads were flushing segments much
faster than the 1 thread could publish them.
> I think this is because publishing segments (DocumentsWriter.publishFlushedSegment) is
actually rather costly (creates CFS file if necessary, writes .si, etc.).
> I committed a workaround for now, to prevent starvation (see svn diff -c 1394704 https://svn.apache.org/repos/asf/lucene/dev/trunk),
but we really should address the root cause by moving these costly ops into flush() so that
publishing is a low cost operation.

--
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

---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@lucene.apache.org
For additional commands, e-mail: dev-help@lucene.apache.org


Mime
View raw message