Subject: Re: Better than..
To: Neil A. Carson <>
From: Manuel Bouyer <>
List: netbsd-advocacy
Date: 01/05/2000 20:53:31
On Wed, Jan 05, 2000 at 06:48:35PM +0000, Neil A. Carson wrote:
> Can't you just moyunt the Linux FS synchronously? In the latest kernels
> I"m pretty sure that behaviour is there. I don't know if it will help save
> your mail or not, though. And people whilttle too much about performance
> to make this the default mount option which is IMHO stupid.

I think it will help, yes. The problem is that this is *synchronous*, it's
not the same a the semi-synchronous which is the default in *BSD (it's the
equivalent of 'mount -o sync' for *BSD). I had a linux box setup this way
and performances were about 1/6 of NetBSD on the same hardware (dual-boot).

What's needed here is not a synchronous filesystem but ordered writes.
*BSD's semi-synchronous is one way to have it, there are other solutions
(e.g. softdep) which combine async speed and semi-synchronous reliability.

Manuel Bouyer, LIP6, Universite Paris VI.