Horton

Display the leader apply worker's PID for parallel apply workers.

Amit Kapila <akapila@postgresql.org>

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Commit: d540a02a724b9643205abce8c5644a0f0908f6e3
Author: Amit Kapila <akapila@postgresql.org>
Date: 2023-01-18T03:33:12Z
Releases: 16.0 
Display the leader apply worker's PID for parallel apply workers.

Add leader_pid to pg_stat_subscription. leader_pid is the process ID of
the leader apply worker if this process is a parallel apply worker. If
this field is NULL, it indicates that the process is a leader apply
worker or a synchronization worker. The new column makes it easier to
distinguish parallel apply workers from other kinds of workers and helps
to identify the leader for the parallel workers corresponding to a
particular subscription.

Additionally, update the leader_pid column in pg_stat_activity as well to
display the PID of the leader apply worker for parallel apply workers.

Author: Hou Zhijie
Reviewed-by: Peter Smith, Sawada Masahiko, Amit Kapila, Shveta Mallik
Discussion: https://postgr.es/m/CAA4eK1+wyN6zpaHUkCLorEWNx75MG0xhMwcFhvjqm2KURZEAGw@mail.gmail.com

Files

PathChange+/−
doc/src/sgml/logical-replication.sgml modified +2 −1
doc/src/sgml/monitoring.sgml modified +26 −10
src/backend/catalog/system_views.sql modified +1 −0
src/backend/replication/logical/applyparallelworker.c modified +3 −3
src/backend/replication/logical/launcher.c modified +47 −17
src/backend/utils/adt/pgstatfuncs.c modified +16 −5
src/include/catalog/catversion.h modified +1 −1
src/include/catalog/pg_proc.dat modified +3 −3
src/include/replication/logicallauncher.h modified +2 −0
src/include/replication/worker_internal.h modified +2 −2
src/test/regress/expected/rules.out modified +2 −1

Documentation touched

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