Subject: Re: Bad performance, biowait on raid device
To: None <>
From: None <>
List: tech-kern
Date: 03/14/2006 15:26:24
In message <>Thor Lancelot Simon writes
>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"?

In a Dell server, a Dell PERC is a reasonable guess (but just a guess).

>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).

Thor, can you suggest any hardware RAID controllers that work well
with NetBSD and are not-awful (or at least, less-awful than most) with
a workload of small, sychronous writes?