The value is chosen to allow only queries that have a reasonable chance
of succeeding, albeit with poor performance because of the high
number of threads.
Testing:
Added a test to make sure that the default value rejects a large query.
Change-Id: I31d3fa3f6305c360922649dba53a9026c9563384
Reviewed-on: http://gerrit.cloudera.org:8080/10628
Reviewed-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
Adds two options: THREAD_RESERVATION_LIMIT and
THREAD_RESERVATION_AGGREGATE_LIMIT, which are both enforced by admission
control based on planner resource requirements and the schedule. The
mechanism used is the same as the minimum reservation checks.
THREAD_RESERVATION_LIMIT limits the total number of reserved threads in
fragments scheduled on a single backend.
THREAD_RESERVATION_AGGREGATE_LIMIT limits the sum of reserved threads
across all fragments.
This also slightly improves the minimum reservation error message to
include the host name.
Testing:
Added end-to-end tests that exercise the code paths.
Ran core tests.
Change-Id: I5b5bbbdad5cd6b24442eb6c99a4d38c2ad710007
Reviewed-on: http://gerrit.cloudera.org:8080/10365
Reviewed-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
