Re: Hot Standby (v9d)

> @@ -1601,6 +1602,24 @@ BufferProcessRecoveryConflictsIfAny(volatile BufferDesc *bufHdr)
> {
> XLogRecPtr bufLSN = BufferGetLSN(bufHdr);
>
> + /*
> + * If the buffer is recent we may need to cancel ourselves
> + * rather than risk returning a wrong answer. This test is
> + * too conservative, but it is correct.
> + *
>>> + * We only need to cancel the current subtransaction.
> + * Once we've handled the error then other subtransactions can
> + * continue processing. Note that we do *not* reset the
> + * BufferRecoveryConflictLSN at subcommit/abort, but we do
> + * reset it if we release our last remaining sbapshot.
> + * see SnapshotResetXmin()
> + *

Is it really enough to cancel just the current subtransaction? What if
it's a serializable transaction?

--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com