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https://issues.apache.org/jira/browse/IMPALA-8737?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Joe McDonnell reassigned IMPALA-8737:
-------------------------------------

    Assignee: Joe McDonnell

> Patch gperftools to fix O(n) scaling in PageHeap::AllocLarge()
> --------------------------------------------------------------
>
>                 Key: IMPALA-8737
>                 URL: https://issues.apache.org/jira/browse/IMPALA-8737
>             Project: IMPALA
>          Issue Type: Bug
>          Components: Backend
>    Affects Versions: Impala 3.3.0
>            Reporter: Joe McDonnell
>            Assignee: Joe McDonnell
>            Priority: Major
>             Fix For: Impala 4.0
>
>
> TCMalloc's PageHeap::AllocLarge() has O( n ) behavior. As the heap gets 
> fragmented, this O( n ) behavior can lead to contention, because the thread 
> executing PageHeap::AllocLarge() is holding a lock. In recent versions of 
> gperftools, this code has been modified to have O(log n) behavior. This could 
> reduce contention significantly in some cases.
> We can get this fix by using a more modern version of gperftools (see 
> https://issues.apache.org/jira/browse/IMPALA-6784 ). However, the patches for 
> the O(log n) behavior are fairly contained. Here are the two patches needed:
> [https://github.com/gperftools/gperftools/commit/06c9414ec423ffe442c047b2560555f9d5847b1d]
> [https://github.com/gperftools/gperftools/commit/f1d3fe4a21e339a3fd6e4592ee7444484a7b92dc]
> These would be easy to port to gperftools-2.5. This Jira tracks that effort 
> (which is separate and would be superseded if we upgrade gperftools). 



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