Thread: pgsql: Keep WAL segments by the flushed value of the slot's restart LSN
pgsql: Keep WAL segments by the flushed value of the slot's restart LSN
From
Alexander Korotkov
Date:
Keep WAL segments by the flushed value of the slot's restart LSN The patch fixes the issue with the unexpected removal of old WAL segments after checkpoint, followed by an immediate restart. The issue occurs when a slot is advanced after the start of the checkpoint and before old WAL segments are removed at the end of the checkpoint. The idea of the patch is to get the minimal restart_lsn at the beginning of checkpoint (or restart point) creation and use this value when calculating the oldest LSN for WAL segments removal at the end of checkpoint. This idea was proposed by Tomas Vondra in the discussion. Unlike 291221c46575, this fix doesn't affect ABI and is intended for back branches. Discussion: https://postgr.es/m/flat/1d12d2-67235980-35-19a406a0%4063439497 Author: Vitaly Davydov <v.davydov@postgrespro.ru> Reviewed-by: Tomas Vondra <tomas@vondra.me> Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Backpatch-through: 13 Branch ------ REL_16_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/cea8f2c3e44b5fac59a7298c6b9045c5cbb0eaeb Modified Files -------------- src/backend/access/transam/xlog.c | 55 ++++++++++++++++++++++++++----- src/backend/replication/logical/logical.c | 10 +++++- src/backend/replication/walsender.c | 4 +++ 3 files changed, 60 insertions(+), 9 deletions(-)