Subject: Re: FFSv1 performance on large filesystems
To: Matthias Scheler <tron@zhadum.de>
From: Greg Oster <oster@cs.usask.ca>
List: tech-kern
Date: 03/23/2005 19:13:49
Matthias Scheler writes:
> On Wed, Mar 23, 2005 at 04:54:12PM -0800, Jason Thorpe wrote:
> > >So measured raw write performance:
> > >
> > >single disk        51MB/Sec
> > >RAIDframe        25MB/Sec
> > >
> > >So it looks to me like RAIDframe really writes to both disk serial and
> > >not parallel.
> > 
> > Is this a RAID-0?  If so, please try ccd(4) and compare.
> 
> No, it's RAID-1. But writes should still happen in parallel there.

They do.

What does your raid0.conf file look like?  I'd expect a RAID 1 set to 
write a little slower than the raw disk, but not this much slower.

I'd also be interested in ccd(4) results (with the same stripe 
widths...)

Later...

Greg Oster