On Thu, Apr 14, 2016 at 1:39 AM, Abhijit Menon-Sen <a...@2ndquadrant.com> wrote: > At 2016-04-12 09:00:57 -0400, robertmh...@gmail.com wrote: >> >> On Mon, Apr 11, 2016 at 1:17 PM, Andres Freund <and...@anarazel.de> wrote: >> > >> > 3) Actually handle the case of the last open segment not being >> > RELSEG_SIZE properly in _mdfd_getseg() - mdnblocks() does so. >> >> #3 seems like it's probably about 15 years overdue, so let's do that >> anyway. > > Do I understand correctly that the case of the "last open segment" > (i.e., the one for which mdfd_chain == NULL) not being RELSEG_SIZE > (i.e., _mdnblocks(reln, forknum, v) < RELSEG_SIZE) should not call > _mfdf_openseg on nextsegno if behaviour is not EXTENSION_CREATE or > InRecovery? > > And that "We won't create segment if not existent" should happen, but > doesn't only because the next segment file wasn't removed earlier, so > we have to add an extra check for that case? > > In other words, is something like the following what's needed here, or > is there more to it?
Something like that is what I was thinking about, but I notice it has the disadvantage of adding lseeks to cater to a shouldn't-happen condition. Not sure if we should care. My attempts to test things were also singularly unrewarding. Even after messing with the filesystem in various ways, I couldn't figure out exactly how this makes a difference. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers