Don't start to think that Bonnie gives real world performance numbers.
It gives single tasking sequential access throughput values. Sure
Bonnie's numbers have some value, but don't think that its results match
typical system access patterns.
The performance difference with Raid-1 is seen when doing several io
bound tasks simultaneously. Bonnie doesn't come close to doing this.
<>< Lance.
[EMAIL PROTECTED] wrote:
> Yes, I guess you're right that the way raid-1 stripes the reads doesn't
> necessarily yield higher read performance after all... Here's a little
> test I did:
>
> raid-0 on two disks:
> -------Sequential Output-------- ---Sequential Input-- --Random--
> -Per Char- --Block--- -Rewrite-- -Per Char- --Block--- --Seeks---
> Machine MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU /sec %CPU
> 900 6160 97.1 21710 73.3 8559 52.5 7841 94.2 23977 63.9 157.3 5.5
>
> raid-1 on the same disks:
> -------Sequential Output-------- ---Sequential Input-- --Random--
> -Per Char- --Block--- -Rewrite-- -Per Char- --Block--- --Seeks---
> Machine MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU /sec %CPU
> 470 5801 94.6 11719 39.5 5264 32.5 6931 83.0 11861 34.8 167.4 4.7
>
> Hmm.... I know that raid-1 does distribute the reads to both disks, so I would
> think that read-performance should increase. But it seems like it doesn't. At
> least not in this case. Btw. the disks where on separate SCSI controllers.
>
