On Wed, 18 Mar 2009, Martijn van Oosterhout wrote:
> Generally PG uses O_SYNC on open
Only if you change wal_sync_method=open_sync. That's the very last option
PostgreSQL will try--only if none of the other are available will it use
that.
Last time I checked the defaults value for that parameter broke down like
this by platform:
open_datasync (O_DSYNC): Solaris, Windows (I think there's a PG wrapper
involved for Win32)
fdatasync: Linux (even though the OS just provides a fake wrapper around
fsync for that call)
fsync_writethrough: Mac OS X
fsync: FreeBSD
That makes the only UNIX{-ish} OS where the default is a genuine sync
write Solaris.
--
* Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD