Thomas Tauber-Marshall has uploaded this change for review. ( http://gerrit.cloudera.org:8080/15860
Change subject: IMPALA-9716: Add jitter to the exponential backoff in status reporting ...................................................................... IMPALA-9716: Add jitter to the exponential backoff in status reporting When status reports fail, we use exponential backoff when retrying sending them. However, currently the backoff is deterministic, leading to a thundering herd problem where all of the backends for a particular query may try to report at the same time, the coordinator is overwhelmed and rejects some of the rpcs, then the backends all backoff by the same amount and retry sending at the same time, leading the coordinator to be overwhelmed again. This patch alleviates this problem by adding some random jitter to the exponential backoff used when a status report fails. Testing: - Passed a full run of existing tests. - Code path is covered by test_reportexecstatus_retries Change-Id: Id05c224517aa606057117328f480dfa98676b923 --- M be/src/runtime/query-state.cc 1 file changed, 9 insertions(+), 1 deletion(-) git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/60/15860/1 -- To view, visit http://gerrit.cloudera.org:8080/15860 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: newchange Gerrit-Change-Id: Id05c224517aa606057117328f480dfa98676b923 Gerrit-Change-Number: 15860 Gerrit-PatchSet: 1 Gerrit-Owner: Thomas Tauber-Marshall <tmarsh...@cloudera.com>
