Fix LOCK_TIMEOUT handling during parallel apply.
Previously, the parallel apply worker used SIGINT to receive a graceful
shutdown signal from the leader apply worker. However, SIGINT is also used
by the LOCK_TIMEOUT handler to trigger a query-cancel interrupt. This
overlap caused the parallel apply worker to miss LOCK_TIMEOUT signals,
leading to incorrect behavior during lock wait/contention.
This patch resolves the conflict by switching the graceful shutdown signal
from SIGINT to SIGUSR2.
Reported-by: Zane Duffield <duffieldzane@gmail.com>
Diagnosed-by: Zhijie Hou <houzj.fnst@fujitsu.com>
Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 16, where it was introduced
Discussion: https://postgr.es/m/CACMiCkXyC4au74kvE2g6Y=mCEF8X6r-Ne_ty4r7qWkUjRE4+oQ@mail.gmail.com
Branch
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REL_18_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/37fc5de438b423f34ba8551a9902a52963be98f5
Modified Files
--------------
src/backend/postmaster/interrupt.c | 5 ++---
src/backend/replication/logical/applyparallelworker.c | 17 ++++++++++++-----
src/backend/replication/logical/launcher.c | 4 ++--
3 files changed, 16 insertions(+), 10 deletions(-)
