Re: FFSv1 performance on large filesystems

On Wed, Mar 23, 2005 at 07:13:49PM -0600, Greg Oster wrote:
> > No, it's RAID-1. But writes should still happen in parallel there.
> They do.

RAIDframe queues them in parallel. But maybe something in the kernel
searilizes them?

> What does your raid0.conf file look like?

The RAID gets autoconfigured. But the configuration file I used for
creating it looked like this:

START array
1 2 0
START disks
/dev/wd0a
/dev/wd1a
START layout
128 1 1 1
START queue
fifo 100

> I'd expect a RAID 1 set to write a little slower than the raw disk,
> but not this much slower.

Yes, me too. It should be slower by the latency it takes to deliver the
write to the second disk. But not by a factor of two.

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

It's not a stripe it's a mirror.

	Kind regards

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