On Mon, Aug 19, 2013 at 09:27:57PM -0400, Stephen Frost wrote: > * Andres Freund (and...@2ndquadrant.com) wrote: > > I vote for adapting the patch to additionally zero out the file via > > write(). In your tests that seemed to perform at least as good as the > > old method... It also has the advantage that we can use it a littlebit > > more as a testbed for possibly using it for heap extensions one day. > > We're pretty early in the cycle, so I am not worried about this too much... > > I dunno, I'm pretty disappointed that this doesn't actually improve > things. Just following this casually, it looks like it might be some > kind of locking issue in the kernel that's causing it to be slower; or > at least some code path that isn't exercise terribly much and therefore > hasn't been given the love that it should. > > Definitely interested in what Ts'o says, but if we can't figure out why > it's slower *without* writing out the zeros, I'd say we punt on this > until Linux and the other OS folks improve the situation.
Agreed. Anyone with an affected kernel really can't be doing performance tests right now, and that isn't good. -- Bruce Momjian <br...@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + It's impossible for everything to be true. + -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
