On Wed, Jun 07, 2006 at 09:34:47AM +0800, Qingqing Zhou wrote: > > "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 :-(
Maybe a comment patch would be in order to prevent future confusion? -- Jim C. Nasby, Sr. Engineering Consultant [EMAIL PROTECTED] Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461 ---------------------------(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
