Tim Armstrong has uploaded a new patch set (#3). Change subject: IMPALA-2800: make memory maintenance less aggressive ......................................................................
IMPALA-2800: make memory maintenance less aggressive Memory maintenance isn't necessary for correctness - the MemTracker GC functions are sufficient to free up memory before a mem limit would be hit. So the main purpose of memory maintenance is to avoid holding onto unneeded memory while the system is idle or under light load. It can also help to redistribute memory between arenas in the buffer pool if they have become imbalanced. Neither of these purposes require the maintenance to be very aggressive aggressive. * Simplify the heuristic for freeing and update the comments to reflect the current reality. * Limit the rate at which TCMalloc releases memory to avoid it holding the global heap lock for a long time. * Increase the memory maintenance interval - 1s is too aggressive and can free memory that will be imminently reused by a running query. Change-Id: I0f822b294ab253d6f2828fc52f353aecaaf9b701 --- M be/src/common/init.cc M be/src/util/memory-metrics.h 2 files changed, 27 insertions(+), 28 deletions(-) git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/26/6626/3 -- To view, visit http://gerrit.cloudera.org:8080/6626 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: newpatchset Gerrit-Change-Id: I0f822b294ab253d6f2828fc52f353aecaaf9b701 Gerrit-PatchSet: 3 Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-Owner: Tim Armstrong <[email protected]> Gerrit-Reviewer: Bharath Vissapragada <[email protected]> Gerrit-Reviewer: Tim Armstrong <[email protected]> Gerrit-Reviewer: anujphadke <[email protected]>
