lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Steve Rowe (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (LUCENE-7868) Use multiple threads to apply deletes and DV updates
Date Thu, 06 Jul 2017 16:19:00 GMT

    [ https://issues.apache.org/jira/browse/LUCENE-7868?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16076820#comment-16076820
] 

Steve Rowe commented on LUCENE-7868:
------------------------------------

For some reason these commit logs didn't get posted here:

{noformat}
Repository: lucene-solr
Updated Branches:
 refs/heads/master f0cc3769b -> 7c704d525


LUCENE-7868: fix race condition when reader pooling is disabled


Project: http://git-wip-us.apache.org/repos/asf/lucene-solr/repo
Commit: http://git-wip-us.apache.org/repos/asf/lucene-solr/commit/7c704d52
Tree: http://git-wip-us.apache.org/repos/asf/lucene-solr/tree/7c704d52
Diff: http://git-wip-us.apache.org/repos/asf/lucene-solr/diff/7c704d52

Branch: refs/heads/master
Commit: 7c704d5258b3be8c383ccb96bf4a30be441f091c
Parents: f0cc376
Author: Mike McCandless <mikemccand@apache.org>
Authored: Wed Jul 5 16:53:05 2017 -0400
Committer: Mike McCandless <mikemccand@apache.org>
Committed: Wed Jul 5 16:53:05 2017 -0400
{noformat}

{noformat}
Repository: lucene-solr
Updated Branches:
 refs/heads/branch_7x 454950aae -> 40dd3efb8


LUCENE-7868: fix race condition when reader pooling is disabled


Project: http://git-wip-us.apache.org/repos/asf/lucene-solr/repo
Commit: http://git-wip-us.apache.org/repos/asf/lucene-solr/commit/40dd3efb
Tree: http://git-wip-us.apache.org/repos/asf/lucene-solr/tree/40dd3efb
Diff: http://git-wip-us.apache.org/repos/asf/lucene-solr/diff/40dd3efb

Branch: refs/heads/branch_7x
Commit: 40dd3efb8fb6b33a3e010e8c3d391d1165bd51e6
Parents: 454950a
Author: Mike McCandless <mikemccand@apache.org>
Authored: Wed Jul 5 16:53:05 2017 -0400
Committer: Mike McCandless <mikemccand@apache.org>
Committed: Wed Jul 5 16:53:33 2017 -0400
{noformat}

{noformat}
Repository: lucene-solr
Updated Branches:
 refs/heads/branch_7_0 ec306dce2 -> 9ec400c4f


LUCENE-7868: fix race condition when reader pooling is disabled


Project: http://git-wip-us.apache.org/repos/asf/lucene-solr/repo
Commit: http://git-wip-us.apache.org/repos/asf/lucene-solr/commit/9ec400c4
Tree: http://git-wip-us.apache.org/repos/asf/lucene-solr/tree/9ec400c4
Diff: http://git-wip-us.apache.org/repos/asf/lucene-solr/diff/9ec400c4

Branch: refs/heads/branch_7_0
Commit: 9ec400c4f69432773edd3678e21c4c08590cddf6
Parents: ec306dc
Author: Mike McCandless <mikemccand@apache.org>
Authored: Wed Jul 5 16:53:05 2017 -0400
Committer: Mike McCandless <mikemccand@apache.org>
Committed: Wed Jul 5 16:54:12 2017 -0400
{noformat}

> Use multiple threads to apply deletes and DV updates
> ----------------------------------------------------
>
>                 Key: LUCENE-7868
>                 URL: https://issues.apache.org/jira/browse/LUCENE-7868
>             Project: Lucene - Core
>          Issue Type: Improvement
>            Reporter: Michael McCandless
>            Assignee: Michael McCandless
>             Fix For: 7.0
>
>         Attachments: cpu-after.png, cpu-before.png, LUCENE-7868.patch, LUCENE-7868.patch,
LUCENE-7868.patch, LUCENE-7868.patch, LUCENE-7868.patch, LUCENE-7868.patch
>
>
> Today, when users delete documents or apply doc values updates, IndexWriter buffers them
up into frozen packets and then eventually uses a single thread (BufferedUpdatesStream.applyDeletesAndUpdates)
to resolve delete/update terms to docids.  This thread also holds IW's monitor lock, so it
also blocks refresh, merges starting/finishing, commits, etc.
> We have heavily optimized this part of Lucene over time, e.g. LUCENE-6161, LUCENE-2897,
LUCENE-2680, LUCENE-3342, but still, it's a single thread so it can't use multiple CPU cores
commonly available now.
> This doesn't affect append-only usage, but for update-heavy users (me!) this can be a
big bottleneck, and causes long stop-the-world hangs during indexing.
> I have an initial exploratory patch to make these lookups concurrent, without holding
IW's lock, so that when a new packet of deletes is pushed, which happens when we flush a new
segment, we immediately use that same indexing thread to and resolve the deletions.
> This is analogous to when we made segment flushing concurrent (LUCENE-3023), just for
deletes and DV updates as well.



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)

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


Mime
View raw message