Subject: Re: Expected SCSI transfer rates?
To: Thomas Klausner <firstname.lastname@example.org>
From: Manuel Bouyer <email@example.com>
Date: 12/23/1999 22:47:06
On Thu, Dec 23, 1999 at 12:38:42AM +0100, Thomas Klausner wrote:
> I'm currently copying files around on NetBSD-1.4.1/i386, and wondered
> why it takes so long. I have a SCSI-only system (Adaptec 2940UW), and
> in this special case I was copying from one disc with an ext2fs to an
> msdos-system on another disc, and got about 300kb/s. When I started
> another copy parallel from the same ext2fs to a 4.2BSD(ffs) partition,
> both transfer rates got down to about 70kb/s each.
The ext2fs implementation in NetBSD doesn't have good performances on NetBSD
because it doesn't uses clustered read/writes. This requires changes to
vfs_cluster.c to handle block sizes smaller than a page size. It's on my to-do
list but not on the top ...
Manuel Bouyer, LIP6, Universite Paris VI. Manuel.Bouyer@lip6.fr