On Thu, Nov 17, 2011 at 7:52 AM, Schubert, Joerg <jschubert@xxxxxxxxxx> wrote: > Hello, > > I have two servers with battery backed power supply (USV). So it is > unlikely, that both will crash at the same time. > > Will synchronous replication work with fsync=off? > That means we will commit to system cache, but not to disk. Data will not > survive a system crash but the second system should still be consistent. > you should never use fsync=off (in production at least) the appropiate parameter to use is synchronous_commit which is the one that controls synchronous replication: off = no local nor remote synchronous commit local = local synchronous commit but no remote on = both, local and remote, synchronous commit synchronous commit = flushed to disk once all that said, i guess you can use fsync on any combination (off on master and on on standby, for your case) but i haven't tried. anyway that will guarantee you will lose your master instalation on OS crash and i think to remember that even if the OS doesn't crash there is a risk (altough i can't find the mail saying that) -- Jaime Casanova www.2ndQuadrant.com Professional PostgreSQL: Soporte 24x7 y capacitación -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
