On Tue, Dec 11, 2007 at 08:18:42AM -0500, Bruce Momjian wrote: > Magnus Hagander wrote: > > On Mon, Dec 10, 2007 at 02:05:05PM +0000, Bruce Momjian wrote: > > > Log Message: > > > ----------- > > > Document how to turn off disk write cache on popular operating systems. > > > > > > Modified Files: > > > -------------- > > > pgsql/doc/src/sgml: > > > wal.sgml (r1.46 -> r1.47) > > > > > > (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/wal.sgml?r1=1.46&r2=1.47) > > > > Should this mention that you don't need to turn it off at the disk level if > > you use fsync_writethrough? > > Uh, I remember we looked at this checkbox before but I don't remember > the details, and I can't find a comment about it. Was the issue that > writethrough always forces through the disk cache? Is that the default > on Win32? Did we comment this somewhere?
If you set it to fsync or fsync_writethrough it will write through the cache. (fsync is just an alias) If you set it to OPEN_DATASYNC, it will respond to the checkbox you are referring to. OPEN_DATASYNC is the default, IIRC. //Magnus ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend