Fix handling of synchronous replication for stopping WAL senders This fixes an oversight from c6c3334 which forgot that if a subset of WAL senders are stopping and in a sync state, other WAL senders could still be waiting for a WAL position to be synced while committing a transaction. However the subset of stopping senders would not release waiters, potentially breaking synchronous replication guarantees. This commit makes sure that even WAL senders stopping are able to release waiters and are tracked properly.
On 9.4, this can also trigger an assertion failure when setting for example max_wal_senders to 1 where a WAL sender is not able to find itself as in synchronous state when the instance stops. Reported-by: Paul Guo Author: Paul Guo, Michael Paquier Discussion: https://postgr.es/m/caeet0zev8vfqt3c-cqm6byob4r4vywcef1j21dox-gcvhcs...@mail.gmail.com Backpatch-through: 9.4 Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/4c703369af3e34cd7289d99c1b6f10e3b3bbbb4d Modified Files -------------- src/backend/replication/syncrep.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-)