[
https://issues.apache.org/jira/browse/SOLR-7319?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14391944#comment-14391944
]
Shawn Heisey commented on SOLR-7319:
------------------------------------
bq. Would it be easily possible to detect the total amount of system memory and
set the max heap to a percentage?
We have the JVM and extensive programming skills available to us. IMHO there's
no reason we can't leverage a very small commandline Java program (rolled into
a jar like jetty uses start.jar) to gather detailed system information,
calculate values and GC tuning options, write them to someplace relevant (the
solr home maybe), and use them in the start script.
> Workaround the "Four Month Bug" causing GC pause problems
> ---------------------------------------------------------
>
> Key: SOLR-7319
> URL: https://issues.apache.org/jira/browse/SOLR-7319
> Project: Solr
> Issue Type: Bug
> Components: scripts and tools
> Affects Versions: 5.0
> Reporter: Shawn Heisey
> Assignee: Shawn Heisey
> Attachments: SOLR-7319.patch, SOLR-7319.patch, SOLR-7319.patch
>
>
> A twitter engineer found a bug in the JVM that contributes to GC pause
> problems:
> http://www.evanjones.ca/jvm-mmap-pause.html
> Problem summary (in case the blog post disappears): The JVM calculates
> statistics on things like garbage collection and writes them to a file in the
> temp directory using MMAP. If there is a lot of other MMAP write activity,
> which is precisely how Lucene accomplishes indexing and merging, it can
> result in a GC pause because the mmap write to the temp file is delayed.
> We should implement the workaround in the solr start scripts (disable
> creation of the mmap statistics tempfile) and document the impact in
> CHANGES.txt.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org
For additional commands, e-mail: dev-h...@lucene.apache.org
