Re: [PATCH 00/19] Hardware Accelerated MD RAID5: Introduction

Jakob Oestergaard
2006-09-14T07:42:46Z

On Wed, Sep 13, 2006 at 12:17:55PM -0700, Dan Williams wrote:
...
> >Out of curiosity; how does accelerated compare to non-accelerated?
>
> One quick example:
> 4-disk SATA array rebuild on iop321 without acceleration - 'top'
> reports md0_resync and md0_raid5 dueling for the CPU each at ~50%
> utilization.
>
> With acceleration - 'top' reports md0_resync cpu utilization at ~90%
> with the rest split between md0_raid5 and md0_raid5_ops.
>
> The sync speed reported by /proc/mdstat is ~40% higher in the accelerated
> case.

Ok, nice :)

>
> That being said, array resync is a special case, so your mileage may
> vary with other applications.

Every-day usage I/O performance data would be nice indeed :)

> I will put together some data from bonnie++, iozone, maybe contest,
> and post it on SourceForge.

Great!

--

/ jakob