On Wed, Dec 15, 2021 at 8:19 AM Masahiko Sawada <sawada.m...@gmail.com> wrote: > > On Tue, Dec 14, 2021 at 2:35 PM Greg Nancarrow <gregn4...@gmail.com> wrote: > > > > On Tue, Dec 14, 2021 at 3:23 PM vignesh C <vignes...@gmail.com> wrote: > > > > > > While the worker is skipping one of the skip transactions specified by > > > the user and immediately if the user specifies another skip > > > transaction while the skipping of the transaction is in progress this > > > new value will be reset by the worker while clearing the skip xid. I > > > felt once the worker has identified the skip xid and is about to skip > > > the xid, the worker can acquire a lock to prevent concurrency issues: > > > > That's a good point. > > If only the last_error_xid could be skipped, then this wouldn't be an > > issue, right? > > If a different xid to skip is specified while the worker is currently > > skipping a transaction, should that even be allowed? > > > > We don't expect such usage but yes, it could happen and seems not > good. I thought we can acquire Share lock on pg_subscription during > the skip but not sure it's a good idea. It would be better if we can > find a way to allow users to specify only XID that has failed. >
Yeah, but as we don't have a definite way to allow specifying only failed XID, I think it is better to use share lock on that particular subscription. We are already using it for add/update rel state (see, AddSubscriptionRelState, UpdateSubscriptionRelState), so this will be another place to use a similar technique. -- With Regards, Amit Kapila.
