On Thursday, June 02, 2011 07:31:33 PM Robert Haas wrote: > On Wed, Jun 1, 2011 at 1:15 PM, Robert Haas <robertmh...@gmail.com> wrote: > > 2011/5/31 Andres Freund <and...@anarazel.de>: > >> On Tuesday, May 31, 2011 03:27:22 Alvaro Herrera wrote: > >>> Excerpts from Andres Freund's message of lun may 30 20:47:49 -0400 2011: > >>> > On Tuesday, May 31, 2011 02:35:58 AM Andres Freund wrote: > >>> > > On Tuesday, May 31, 2011 02:14:00 AM Andres Freund wrote: > >>> > > > On Tuesday, May 31, 2011 01:56:05 AM Cédric Villemain wrote: > >>> > > > > I remove my own explanations as we conclude on the same thing. > >>> > > > > Attached is the fix by adding a (!reindex) in the index.c > >>> > > > > if(). > >>> > > > > >>> > > > Thats imo wrong because it will break a plain REINDEX? > >>> > > > >>> > > > I think one possible correct fix would be the attached: > >>> > > My version was wrong as well because it did not observe > >>> > > RelationTruncate's nblocks argument. That function is used to > >>> > > "shorten" the relation in vacuum. So dropping the init fork there > >>> > > is not a good idea. > >>> > > > >>> > > So I think it is the simpler version of simply checking the > >>> > > existance of the fork before creating is ok. > >>> > >>> Hmm, I wonder if what we should be doing here is observe isreindex in > >>> index_build to avoid creating the init fork. Doing smgr access at that > >>> level seems wrong. > >> > >> isreindex doesn't contain the necessary informormation as its set doing > >> a REINDEX even though a new relfilenode is created and thus the fork > >> needs to be created. > >> > >> It doesn't seem terribly clean do do the !smgrexists(), I aggree with > >> you there. On the other hand we are calling smgrcreate() two lines down > >> anyway. I personally don't realy like the placement of that piece of > >> code very much. Doing it in index_build seems to be the wrong place. I > >> don't think there really is a good place for it right now. > > > > I'm open to suggestions on how to rearrange this, but I think for > > right now the approach you proposed upthread (add a smgrexists() test) > > is probably the simplest way to fix this. > > Done. Your patch tested for FSM_FORKNUM instead of INIT_FORKNUM, > which seemed wrong, so I changed it. I also added comments. Wow. I don't think I ever made so many stupid mistakes when doing a two line change. I abviously wasn't really awake that evening. As evidenced excessively in that thread ;)
Thanks, Andres -- Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-bugs
