[ https://issues.apache.org/jira/browse/IMPALA-4555?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Thomas Tauber-Marshall reassigned IMPALA-4555: ---------------------------------------------- Assignee: Thomas Tauber-Marshall (was: Michael Ho) > Don't cancel query for failed ReportExecStatus (done=false) RPC > --------------------------------------------------------------- > > Key: IMPALA-4555 > URL: https://issues.apache.org/jira/browse/IMPALA-4555 > Project: IMPALA > Issue Type: Sub-task > Components: Distributed Exec > Affects Versions: Impala 2.7.0 > Reporter: Sailesh Mukil > Assignee: Thomas Tauber-Marshall > Priority: Major > > We currently try to send the ReportExecStatus RPC up to 3 times if the first > 2 times are unsuccessful - due to high network load or a network partition. > If all 3 attempts fail, we cancel the fragment instance and hence the query. > However, we do not need to cancel the fragment instance if sending the report > with _done=false_ failed. We can just skip this turn and try again the next > time. > We could probably skip sending the report up to 2 times (if we're unable to > send due to high network load and if done=false) before succumbing to the > current behavior, which is to cancel the fragment instance. The point is to > try at a later time when the network load may be lower rather than try > quickly again. The chance that the network load would reduce in 100 ms is > less than in 5s. > Also, we probably do not need to have the retry logic unless we've already > skipped twice or if done=true. > This could help reduce the network load on the coordinator for highly > concurrent workloads. > The only drawback I see now is that the QueryExecSummary might be stale for a > while (which it would have anyway because the RPCs would have failed to send) > P.S: This above proposed solution may need to change if we go ahead with > IMPALA-2990. -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-all-unsubscr...@impala.apache.org For additional commands, e-mail: issues-all-h...@impala.apache.org