On Mon, Apr 16, 2012 at 1:58 PM, Simon Riggs <si...@2ndquadrant.com> wrote: > If we do need to do something, then introduce concept of a visibility > conflict. > > On replay: > If feedback not set, set LSN of visibility conflict on PROCs that > conflict, if not already set. > > On query: > If feedback not set, check conflict LSN against page, if page is > later, check visibility.
Hmm, should have read the whole thread before replying. This similar to what I just proposed in response to Heikki's message, but using LSN in lieu of (or maybe you mean in addition to) XID. I don't think we can ignore the need to throw conflicts just because hot_standby_feedback is set; there are going to be corner cases, for example, when it's just recently been turned on and the master has already done cleanup; or if the master and standby have recently gotten disconnected for even just a few seconds. But fundamentally we all seem to be converging on some variant of the "soft conflict" idea. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
