On Thu, Feb 3, 2022 at 1:48 PM David G. Johnston <david.g.johns...@gmail.com> wrote: > > On Wednesday, February 2, 2022, Masahiko Sawada <sawada.m...@gmail.com> wrote: >> >> and have other error >> information in pg_stat_subscription_workers view. > > > What benefit is there to keeping the existing collector-based > pg_stat_subscripiton_workers view? If we re-write it using shmem IPC then we > might as well put everything there and forego using a catalog. Then it > behaves in a similar manner to pg_stat_activity but for logical replication > workers.
Yes, but if we use shmem IPC, we need to allocate shared memory for them based on the number of subscriptions, not logical replication workers (i.e., max_logical_replication_workers). So we cannot estimate memory in the beginning. Also, IIUC the number of subscriptions that are concurrently working is limited by max_replication_slots (see ReplicationStateCtl) but I think we need to remember the state of disabled subscriptions too. Regards, -- Masahiko Sawada EDB: https://www.enterprisedb.com/
