Drop replication origin slots before tablesync worker exits.
Currently, the replication origin tracking of the tablesync worker is
dropped by the apply worker. So, there will be a small lag between the
tablesync worker exit and its origin tracking got removed. In the
meantime, new tablesync workers can be launched and will try to set up
a new origin tracking. This can lead the system to reach max configured
limit (max_replication_slots) even if the user has configured the max
limit considering the number of tablesync workers required in the system.
We decided not to back-patch as this can occur in very narrow
circumstances and users have to option to increase the configured limit by
increasing max_replication_slots.
Reported-by: Hubert Depesz Lubaczewski
Author: Ajin Cherian
Reviwed-by: Masahiko Sawada, Peter Smith, Hou Zhijie, Amit Kapila
Discussion: https://postgr.es/m/20220714115155.GA5439@depesz.com
Branch
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master
Details
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https://git.postgresql.org/pg/commitdiff/f6c5edb8abcac04eb3eac6da356e59d399b2bcef
Modified Files
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src/backend/commands/subscriptioncmds.c | 25 ++++++++-------
src/backend/replication/logical/tablesync.c | 50 ++++++++++++++++-------------
2 files changed, 41 insertions(+), 34 deletions(-)