Subject: Re: Bad performance, biowait on raid device
To: None <firstname.lastname@example.org>
From: Pavel Cahyna <email@example.com>
Date: 03/14/2006 23:31:45
On Tue, Mar 14, 2006 at 05:28:41PM -0500, Thor Lancelot Simon wrote:
> On Tue, Mar 14, 2006 at 06:09:51PM +0100, Stefan Wurstbauer wrote:
> > Hi all,
> > I'm running NetBSD 3.0 on a Dell PowerEdge 4600 server. The disks are
> > 4 scsi disks / raid 5 on a hardware raid controller, mounted as a ffs
> > filesystem (without softdeps).
> > When I, for example, extract pkgsrc.tgz I take ages to complete.
> *What* disks? *What* "hardware RAID controller"?
> A lot of hardware RAID controllers are really quite awful, especially
> for small, synchronous writes (which is what you'll get, with FFS
> without softdep).
What hardware RAID controllers are "quite awful"?
Also, wouldn't 3 or 5 disks give better performance?