Remove unnecessary dependency on statement_timeout in prepared_xacts test.
Rather than waiting around for statement_timeout to expire, we can just
try to take the table's lock in nowait mode. This saves some fraction
under 4 seconds when running this test with prepared xacts available,
and it guards against timeout-expired-anyway failures on very slow
machines when prepared xacts are not available, as seen in a recent
failure on axolotl for instance.
This approach could fail if autovacuum were to take an exclusive lock
on the test table concurrently, but there's no reason for it to do so.
Since the main point here is to improve stability in the buildfarm,
back-patch to all supported branches.
Branch
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REL9_2_STABLE
Details
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http://git.postgresql.org/pg/commitdiff/f6396dce0f15e31229d4d3c9285bdc5995b55ce1
Modified Files
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src/test/regress/expected/prepared_xacts.out | 10 ++++------
src/test/regress/expected/prepared_xacts_1.out | 14 ++------------
src/test/regress/sql/prepared_xacts.sql | 6 ++----
3 files changed, 8 insertions(+), 22 deletions(-)