On Tue, 2010-04-27 at 17:24 -0400, Tom Lane wrote: > Isn't the snapshotOldestActiveXid filter in > RecordKnownAssignedTransactionIds completely wrong/useless/bogus? > > AFAICS, snapshotOldestActiveXid is only set once at the start of > recovery. This means it will soon be too old to provide any useful > filtering. But what's far worse is that the XID space will eventually > wrap around, and that test will start filtering *everything*. > > I think we should just lose that test, as well as the variable.
Yes, though it looks like it is still necessary in creating a valid initial state because otherwise we may have xids in KnownAssigned array that are already complete. The comment there talks about wasting memory, though it appears to be a correctness issue. So perhaps a similar test is required in ProcArrayApplyRecoveryInfo() but not in RecordKnownAssignedTransactionIds(). That way it is applied, but only once at initialisation. -- Simon Riggs www.2ndQuadrant.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
