On Fri, Aug 19, 2022 at 7:10 PM Amit Kapila <amit.kapil...@gmail.com> wrote: > > On Fri, Aug 19, 2022 at 2:36 PM Peter Smith <smithpb2...@gmail.com> wrote: > > > > Here are my review comments for the v23-0005 patch: > > > > ====== > > > > Commit Message says: > > main_worker_pid is Process ID of the main apply worker, if this process is a > > apply background worker. NULL if this process is a main apply worker or a > > synchronization worker. > > The new column can make it easier to distinguish main apply worker and apply > > background worker. > > > > -- > > > > Having a column called ‘main_worker_pid’ which is defined to be NULL > > if the process *is* the main apply worker does not make any sense to > > me. > > > > I haven't read this part of a patch but it seems to me we have > something similar for parallel query workers. Refer 'leader_pid' > column in pg_stat_activity. >
IIUC (from the patch 0005 commit message) the intention is to be able to easily distinguish the worker types. I thought using a leader PID (by whatever name) seemed a poor way to achieve that in this case because the PID is either NULL or not NULL, but there are 3 kinds of subscription workers, not 2. ------ Kind Regards, Peter Smith. Fujitsu Australia