Magnus Hagander wrote:
> > > 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.
OK, docs updated:
On <productname>Windows</> if <varname>wal_sync_method</> is <literal>open_datasync</> (the default), write caching
isdisabled by unchecking <literal>My Computer\Open\{select disk drive}\Properties\Hardware\Properties\Policies\Enable
writecaching on the disk</>. Also on Windows, <literal>fsync</> and <literal>fsync_writethrough</> never do write
caching.
-- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB
http://postgres.enterprisedb.com
+ If your life is a hard drive, Christ can be your backup. +