[jira] [Commented] (TEZ-4157) ShuffleHandler: upgrade to netty4

["László Bodor (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/TEZ-4157?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17318429#comment-17318429 ] 

László Bodor commented on TEZ-4157:
-----------------------------------

moving this change to a pull request

> ShuffleHandler: upgrade to netty4
> ---------------------------------
>
>                 Key: TEZ-4157
>                 URL: https://issues.apache.org/jira/browse/TEZ-4157
>             Project: Apache Tez
>          Issue Type: Bug
>            Reporter: László Bodor
>            Assignee: László Bodor
>            Priority: Major
>         Attachments: TEZ-4157.01.patch, TEZ-4157.02.patch, TEZ-4157.03.patch, TEZ-4157.04.patch, TEZ-4157.05.patch, TEZ-4157.06.patch
>
>          Time Spent: 10m
>  Remaining Estimate: 0h
>
> -In the dependency tree, there are 2 occurrences of compile scope direct netty dependencies, however, they're not used at all. I compiled locally successfully without them. E.g. when investigating blackduck alerts (complaining about netty deps for current 3.10.5.Final), it would be cleaner to start from a dependency tree where Tez doesn't depend on netty directly in order to eliminate its responsibility (and move the focus to underlying hadoop for instance).-
> Tez depends on netty3 almost only in ShuffleHandler and some related classes. We can eliminate netty3 by upgrading it, but this effort might involve some testing due to fundamental [changes from netty3->netty4|https://netty.io/wiki/new-and-noteworthy-in-4.0.html] + we don't have a reference yet, as [hadoop's ShuffleHandler|https://github.com/apache/hadoop/blob/trunk/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-shuffle/src/main/java/org/apache/hadoop/mapred/ShuffleHandler.java] is still on netty3.
> As per the netty documentation, we can also expect some performance improvement (e.g. Pooled buffers).
> Background:
> netty4 migration guideline: https://netty.io/wiki/new-and-noteworthy-in-4.0.html
> articles of possible performance improvement:
> https://blog.twitter.com/engineering/en_us/a/2013/netty-4-at-twitter-reduced-gc-overhead.html
> https://developer.squareup.com/blog/upgrading-a-reverse-proxy-from-netty-3-to-4/
>  



--
This message was sent by Atlassian Jira
(v8.3.4#803005)