Subject: Re: Extremely slow IO response times + panic on 3.0_BETA
To: None <port-i386@NetBSD.org>
From: Matthias Scheler <tron@zhadum.de>
List: port-i386
Date: 07/19/2005 21:31:57
In article <x4fyukgdk1.fsf@puuhamaa.af.iki.fi>,
	Valtteri Vuorikoski <vuori@sci.fi> writes:
> I've been running 3.0_BETA CVS'd Jun 30 on a P4 box with two PATA drives
> mirrored with raidframe. When doing disk io that involves heavy metadata
> operations, (ie. tar xzf pkgsrc.tar.gz) sometimes disk IO response gets
> extremely slow.

RAIDframe definitely contributes to this problem because filesystem writes
on RAIDframe mirrors are slow. Have a look here for numbers:

	http://mail-index.netbsd.org/tech-perform/2005/07/06/0000.html

I've bought an Intel SRCS14L RAID controller in the meantime which fixes
that problem completely. Here are the times my P4 needs to extract
NetBSD current source on an empty filesystem not using soft dependeces:

Serial ATA 160GB disk					3:32.38 min
RAIDframe mirror on two Serial ATA 160GB disks		7:39.86 min
Hardware RAID 1 on two Serial ATA 250GB disks		2:47.00 min

	Kind regards

-- 
Matthias Scheler                                  http://scheler.de/~matthias/