On Fri, Apr 30, 2021 at 7:12 AM Thomas Munro <thomas.munro@xxxxxxxxx> wrote: > But do you have lots of short overlapping transactions so that there > is never a moment where there are zero transactions running? Yeah, that almost certainly explains it. Thanks very much for the explanation about the summarized locks. > The number of SERIALIZABLEXACT objects is (max_connections + > max_prepared_transactions) * 10. So, you could try increasing > max_connections (without increasing the actual number of connections) > to see if you can get to a point where you don't see these invalid > virtual xids, and then maybe it'll be able to clean up locks more > aggressively. Aha! I hadn't considered that some parameter besides max_pred_locks_per_transaction would come into play. I'll give this a shot. Thanks, Mike
