Simon Riggs wrote: > On Wed, 2009-09-23 at 11:13 +0300, Heikki Linnakangas wrote: >> I note that we don't emit RunningXacts after a shutdown checkpoint. So >> if recovery starts at a shutdown checkpoint, we don't let read-only >> backends in until the first online checkpoint. Could we treat a shutdown >> checkpoint as a snapshot with no transactions running? Or do prepared >> transactions screw that up? > > We could, but I see no requirement for starting HS from a backup taken > on a shutdown database. It's just another special case to test and since > we already have significant number of important test cases I'd say add > this later.
There's also a related issue that if a backend holding AccessExclusiveLock crashes without writing an abort WAL record, the lock is never released in the standby. We handle the expiration of xids at replay of running-xacts records, but AFAICS we don't do that for locks. It shouldn't be much code to clear those states at shutdown checkpoint, just a few lines to call the right functions methinks. -- Heikki Linnakangas EnterpriseDB http://www.enterprisedb.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
