On Wed, Apr 27, 2016 at 11:51 AM, Andres Freund <and...@anarazel.de> wrote: > On 2016-04-27 14:27:33 +0900, Michael Paquier wrote: >> On Wed, Apr 27, 2016 at 12:25 AM, Robert Haas <robertmh...@gmail.com> wrote: >> > In other words, I think Masahiko Sawada's patch in the original post >> > is pretty much right on target, except that we don't need to do that >> > always, but rather only in the FPI case when the call to >> > visibilitymap_pin() is being optimized away. If we solve the problem >> > that way, I don't think we even need a new WAL record for this case, >> > which is a non-trivial fringe benefit. >> >> The visibility map is not the only thing that need to be addressed, >> no? > > If I understand Robert correctly his point is about fixing the smgr > inval alone - without the invalidation fix that'd not be enough because > the relcache info with outdated information (particularly relallvisible > et al), would continue to be valid. Relcache invalidations imply an smgr > one, but not the other way round. > > The reason the fix for nmsg > 0 && !markXidCommitted isn't entirely > sufficient is because the smgr invalidation isn't transaction bound, > i.e. sent out immediately. So, to have the same behaviour on master/HS, > we need a way to send out the invalidiation properly in lockstep with > replay.
What I'm confused about here is: Masahiko Sawada posted a patch that fixes the problem for him, which does not involve any new WAL record type. It also seems to be fixing the problem in a way that is clean and consistent with what we've done elsewhere. The patch actually under discussion here manages to introduce a new WAL record type without fixing that problem. Therefore I include that the committed patch fixes some *other* problem, not the one that this thread is ostensibly about. -- 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
