Joe McDonnell created IMPALA-8737:
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Summary: 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
Affects Versions: Impala 3.3.0
Reporter: Joe McDonnell
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(which is separate and would be superseded if we upgrade gperftools).
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