Subject: Re: ext2fs is in the tree
To: None <>
From: John S. Dyson <>
List: current-users
Date: 06/11/1997 13:23:18
> Ken Hornstein writes:
> > >Linux's ext2fs has a serious flaw in it -- it does not do synchronous
> > >metadata writes, ever. You derived our ext2fs from ffs -- does that
> > >mean that we properly do synchronous metadata writes, and can claim to
> > >do ext2fs better than Linux does?
> > 
> > Depends what the definition of "better" is.  Linux advocates claim
> > that non-synchronous metadata writes is a feature, and is a big
> > performance gain.  I'm not a filesystem guru, nor do I claim to be
> > one on TV, so I can't evaluate this claim on any technical merits.
> > What do other people think?
> Sure, running without sync metadata writes "improves performance".
> Similarly, if you dump all the safety equipment from an airliner, it
> runs much more "efficiently" thanks to all the saved weight.
> I understand that you can gain substantial weight savings and
> increases in fuel efficiency by removing all the safety features on
> automobiles, too.
I tend to agree with you.  There are times and places where async metadata
are useful.  However it is very unwise to use it on important data.  DOW
will help the situation in the near future on FreeBSD (and I would hope
NetBSD/OpenBSD also.)