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ASF subversion and git services commented on IMPALA-13012: ---------------------------------------------------------- Commit 73f13f0e9f225400bb641c48da57a9871b5d8383 in impala's branch refs/heads/branch-4.4.0 from Michael Smith [ https://gitbox.apache.org/repos/asf?p=impala.git;h=73f13f0e9 ] IMPALA-13012: Lower default query_log_max_queued Sets the query_log_max_queued default such that query_log_max_queued * num_columns(49) < statement_expression_limit to avoid triggering e.g. AnalysisException: Exceeded the statement expression limit (250000) Statement has 370039 expressions. Also increases statement_expression_limit for insertion to avoid an error if query_log_max_queued is changed. Logs time taken to write to the queries table for help with debugging and adds histogram "impala-server.completed-queries.write-durations". Fixes InternalServer so it uses 'default_query_options'. Change-Id: I6535675307d88cb65ba7d908f3c692e0cf3259d7 Reviewed-on: http://gerrit.cloudera.org:8080/21351 Reviewed-by: Michael Smith <michael.sm...@cloudera.com> Tested-by: Michael Smith <michael.sm...@cloudera.com> Reviewed-by: Riza Suminto <riza.sumi...@cloudera.com> (cherry picked from commit ba32d70891fd68c5c1234ed543b74c51661bf272) > Completed queries write fails regularly under heavy load > -------------------------------------------------------- > > Key: IMPALA-13012 > URL: https://issues.apache.org/jira/browse/IMPALA-13012 > Project: IMPALA > Issue Type: Bug > Components: Backend > Affects Versions: Impala 4.4.0 > Reporter: Michael Smith > Assignee: Michael Smith > Priority: Critical > Fix For: Impala 4.4.0 > > > Under heavy test load (running EE tests), Impala regularly fails to write > completed queries with errors like > {code} > W0411 19:11:07.764967 32713 workload-management.cc:435] failed to write > completed queries table="sys.impala_query_log" record_count="10001" > W0411 19:11:07.764983 32713 workload-management.cc:437] AnalysisException: > Exceeded the statement expression limit (250000) > Statement has 370039 expressions. > {code} > After a few attempts, it floods logs with an error for each query that could > not be written > {code} > E0411 19:11:24.646953 32713 workload-management.cc:376] could not write > completed query table="sys.impala_query_log" > query_id="3142ceb1380b58e6:715b83d900000000" > {code} > This seems like poor default behavior. Options for addressing it: > # Decrease the default for {{query_log_max_queued}}. Inserts are pretty > constant at 37 expressions per entry. I'm not sure why that isn't 49, since > that's the number of columns we have; maybe some fields are frequently > omitted. I would cap {{query_log_max_queued}} to {{statement_expression_limit > / number_of_columns ~ 5100}}. > # Allow workload management to {{set statement_expression_limit}} higher > using a similar formula. This may be relatively safe as the expressions are > simple. > # Ideally we would skip expression parsing and construct TExecRequest > directly, but that's a much larger effort. -- This message was sent by Atlassian Jira (v8.20.10#820010) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-all-unsubscr...@impala.apache.org For additional commands, e-mail: issues-all-h...@impala.apache.org