Re: TAKE - make "osyncisdsync" the default

[Andrew Morton <akpm@zip.com.au>]

Stephen Lord wrote:
> 
> Andrew Morton wrote:
> 
> >Eric Sandeen wrote:
> >
> >>"osyncisdsync" makes us go faster, and it's how other Linux
> >>filesystems are set up, anyway - so make it the default.
> >>
> >
> >The comment lies :)
> >
> >        /* For now, when the user asks for O_SYNC, we'll actually
> >         * provide O_DSYNC. */
> >        if (status >= 0) {
> >                if ((file->f_flags & O_SYNC) || IS_SYNC(inode))
> >                        status = generic_osync_inode(inode, OSYNC_METADATA|OSYNC_DATA);
> >        }
> >
> >On other filesystems, O_SYNC writes actually sync both metadata
> >and data, as well as the inode, if i_size changed.
> >
> >For default behaviour I suggest the best semantics are for
> >an O_SYNC write to guarantee that the written data will be
> >available after a crash.
> >
> 
> Ah, but we do not go there:
> 

Now I'm lost.  Eric's commit message seems to indicate that
other filesystems do not sync metadata with O_SYNC, which
isn't the case.

What is the proposed XFS behaviour with O_SYNC??

Thanks.