impala-reviews mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Thomas Tauber-Marshall (Code Review)" <ger...@cloudera.org>
Subject [Impala-ASF-CR] IMPALA-4566: Kudu client glog contention can cause timeouts
Date Sat, 03 Dec 2016 01:04:45 GMT
Thomas Tauber-Marshall has uploaded a new patch set (#2).

Change subject: IMPALA-4566: Kudu client glog contention can cause timeouts
......................................................................

IMPALA-4566: Kudu client glog contention can cause timeouts

Under stressful workloads, there appears to be significant contention
in glog resulting from Kudu logging, causing timeouts and failed
queries.

An easy solution for now is to downgrade Kudu WARNINGs to INFOs as
WARNINGs grab a lock to flush the log. This is appropriate as Kudu
logs WARNINGs much more frequently than Impala and for things that
Impala would normally consider INFO-level.

Testing: Manually verified that the patch redirects Kudu WARNINGs
to the INFO log. Not tested under stress to verify if this actually
solves the contention problem.

Change-Id: Ie535d89ec2525232d4f6a29dd44f51cd6e18a0d2
---
M be/src/exec/kudu-util.cc
1 file changed, 4 insertions(+), 2 deletions(-)


  git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/34/5334/2
-- 
To view, visit http://gerrit.cloudera.org:8080/5334
To unsubscribe, visit http://gerrit.cloudera.org:8080/settings

Gerrit-MessageType: newpatchset
Gerrit-Change-Id: Ie535d89ec2525232d4f6a29dd44f51cd6e18a0d2
Gerrit-PatchSet: 2
Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-Owner: Thomas Tauber-Marshall <tmarshall@cloudera.com>
Gerrit-Reviewer: Dan Hecht <dhecht@cloudera.com>
Gerrit-Reviewer: Matthew Jacobs <mj@cloudera.com>

Mime
View raw message