Re: wake up logical workers after ALTER SUBSCRIPTION

Hi Nathan,

@@ -410,6 +411,12 @@ ExecRenameStmt(RenameStmt *stmt)
>     stmt->newname);
>   table_close(catalog, RowExclusiveLock);
>
> + /*
> + * Wake up the logical replication workers to handle this
> + * change quickly.
> + */
> + LogicalRepWorkersWakeupAtCommit(address.objectId);


Is it really necessary to wake logical workers up when renaming other than
subscription or publication? address.objectId will be a valid subid only
when renaming a subscription.

@@ -322,6 +323,9 @@ UpdateSubscriptionRelState(Oid subid, Oid relid, char
> state,
>
>   /* Cleanup. */
>   table_close(rel, NoLock);
> +
> + /* Wake up the logical replication workers to handle this change
> quickly. */
> + LogicalRepWorkersWakeupAtCommit(subid);


I wonder why a wakeup call is needed every time a subscription relation is
updated.
It seems to me that there are two places where UpdateSubscriptionRelState
is called and we need another worker to wake up:
- When a relation is in SYNCWAIT state, it waits for the apply worker to
wake up and change the relation state to CATCHUP. Then tablesync worker
needs to wake up to continue from CATCHUP state.
- When the state is SYNCDONE and the apply worker has to wake up to change
the state to READY.

I think we already call logicalrep_worker_wakeup_ptr wherever it's needed
for the above cases? What am I missing here?

Best,
--
Melih Mutlu
Microsoft