Subject: Re: comparing raid-like filesystems
To: Thor Lancelot Simon <firstname.lastname@example.org>
From: Jukka Marin <email@example.com>
Date: 02/01/2003 10:04:25
On Sat, Feb 01, 2003 at 12:24:12AM -0500, Thor Lancelot Simon wrote:
> 2) It's just plain *astounding* how inefficient some of those
> implementations are. On hardware with comparable memory bandwidth
> and CPU cycles available, *and lacking hardware XOR support*, with
> the same disks, RAIDframe is often considerably faster. I have
> never understood how some RAID vendors' firmware can consistently
> perform so poorly.
I have no experience of the RAID controllers, but I'm not particularly
happy with the NetBSD RAIDframe implementation. I bought fast disks,
configured RAID - and found out that RAID drops the performance to a
fraction of that of the disks.
I don't know why, because when RAID is 100% busy, CPU load is almost
zero and the disk load 25% or so. It's like if RAIDframe had some
usleep() calls in the code to make things go slower..