Thread: pgsql: Fix autovacuum launcher shutdown sequence

pgsql: Fix autovacuum launcher shutdown sequence

From
Alvaro Herrera
Date:
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
------
REL9_1_STABLE

Details
-------
http://git.postgresql.org/pg/commitdiff/cf5d3f27484177cc4a44ec2bcdd786c9b8e59746

Modified Files
--------------
src/backend/postmaster/autovacuum.c |   16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)