Fix autovacuum launcher shutdown sequence
It was previously possible to have the launcher re-execute its main loop
before shutting down if some other signal was received or an error
occurred after getting SIGTERM, as reported by Qingqing Zhou.
While investigating, Tom Lane further noticed that if autovacuum had
been disabled in the config file, it would misbehave by trying to start
a new worker instead of bailing out immediately -- it would consider
itself as invoked in emergency mode.
Fix both problems by checking the shutdown flag in a few more places.
These problems have existed since autovacuum was introduced, so
backpatch all the way back.
Branch
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REL9_4_STABLE
Details
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http://git.postgresql.org/pg/commitdiff/ec01c1c0a4b3992852f7e1980915f0869498ff69
Modified Files
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src/backend/postmaster/autovacuum.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)