"Qingqing Zhou" <[EMAIL PROTECTED]> wrote > > The overall performance improvement might be marginal but why not if it is > right. What I cares is the correctness. As I understand, the orginal code > puts a shared lock (1) to prevent the vacuum process to move tuples around > so the hint bits change may happen in a wrong place; (2) to prevent other > operations holding EXCLUSIVE lock to change bits at the same time. >
I realized I made an aweful mistake. The shared lock also (3) to prevent other operations holding EXCLUSIVE lock to change the xid fields at the same. So the final conclusion is: the original code is right and my patch is terriblly wrong :-( Regards, Qingqing ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly