[
https://issues.apache.org/jira/browse/HADOOP-15554?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16530148#comment-16530148
]
Andrew Wang commented on HADOOP-15554:
--------------------------------------
I'm guessing the checkstyle difference is because of HADOOP-15252 which
upgraded the version. I just backported that to branch-3.0, so we should be
good for future backports.
Thanks for working on this Todd and Gergo, and Jonathan for reviewing. I'll go
ahead and commit all of these based on Jonathan's +1.
> Improve JIT performance for Configuration parsing
> -------------------------------------------------
>
> Key: HADOOP-15554
> URL: https://issues.apache.org/jira/browse/HADOOP-15554
> Project: Hadoop Common
> Issue Type: Improvement
> Components: conf, performance
> Affects Versions: 3.0.0
> Reporter: Todd Lipcon
> Assignee: Todd Lipcon
> Priority: Minor
> Attachments: HADOOP-15554.branch-3.0.patch,
> HADOOP-15554.branch-3.0.patch, hadoop-15554.patch, hadoop-15554.patch
>
>
> In investigating a performance regression for small tasks between Hadoop 2
> and Hadoop 3, we found that the amount of time spent in JIT was significantly
> higher. Using jitwatch we were able to determine that, due to a combination
> of switching from DOM to SAX style parsing and just having more configuration
> key/value pairs, Configuration.loadResource is now getting compiled with the
> C2 compiler and taking quite some time. Breaking that very large function up
> into several smaller ones and eliminating some redundant bits of code
> improves the JIT performance measurably.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
