Re: ext3-2.4-0.9.4

[Linus Torvalds]

On Thu, 26 Jul 2001, Richard A Nelson wrote:
>
> In looking at the synchronous directory options, I'm unsure as to
> the 'real' status wrt fsync() on a directory:
> 	1) Does fsync() of a directory work on most/all current FS?

Modulo bugs, yes.

Now, there's another issue, of course: if you have an important mail-spool
on some of the less tested filesystems, I would consider you crazy
regardless of fsync() working ;). I don't think anybody has ever verified
that fsync() (or much anything else wrt writing) does the right thing on
NTFS, for example.

> 	2) Does it work on 2.2.x as well as 2.4.x?

Yes. However, there may be performance issues. As with just about
anything, we didn't start optimizing things until it became a real issue,
and in some cases at least historically the filesystems fell back on just
doing a whole "fsync_dev()" if they had nothing better to do.

I think later 2.2.x kernels (ie the ones past the point where Alan took
over) probably have the fsync() optimizations at least for ext2.

		Linus