Tim Armstrong has uploaded this change for review. ( http://gerrit.cloudera.org:8080/10789
Change subject: IMPALA-6425: reduce MemPool max chunk size ...................................................................... IMPALA-6425: reduce MemPool max chunk size IMPALA-2742 capped chunk size doubling to 1MB with the idea that 1MB would be a good value to amortise malloc() overhead. As it turns out, 1MB allocations are significantly more expensive than smaller allocations because they don't have a central freelist in TCMalloc, so the previous choice was misinformed. Note that this doesn't prevent larger allocations from being served from the MemPool, it just caps the automatic doubling behaviour. Perf: Ran single-node TPC-H and targeted perf with scale factor 60. Overall improvement in mean/geomean of 0-2% and no regressions outside of the usual variance. Change-Id: I58cc3031ce592892cb9efe9ab41f07d86468b08c --- M be/src/runtime/mem-pool.h 1 file changed, 3 insertions(+), 2 deletions(-) git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/89/10789/1 -- To view, visit http://gerrit.cloudera.org:8080/10789 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: newchange Gerrit-Change-Id: I58cc3031ce592892cb9efe9ab41f07d86468b08c Gerrit-Change-Number: 10789 Gerrit-PatchSet: 1 Gerrit-Owner: Tim Armstrong <[email protected]>
