Disk I/O Performance with CCD

[Josh Paetzel]

On Tuesday 19 October 2004 19:22, Kristofer Pettijohn wrote:
> Im looking for some suggestions on I/O performance.
>
> I'm using FreeBSD 4.10-RELEASE on a Usenet transit server running
> Diablo for the transit software.
>
> I have 4 Seagate ST373435LC SCSI drives, 70GB each, and I am using
> CCD to bind them together with RAID-0 stripes.
>
> I can pull in anywhere from 30-40 MB sec and push out ~ 8-15
> MB/sec.. averaging about 50 MB/sec throughput.. feeds coming in are
> coming in just fine, but sending stuff back out is lagging behind..
> its falling about a half hour behind every hour.

> Maybe I'm just missing something small, but on these SCSI drives
> which have 160 MB/s transfer rates, I'm expecting a bit more than
> I'm getting with CCD.
>

> Can someone give me any pointers to look at or suggestions of
> things to try?
>
> Thanks!
>
> Kristofer

I don't know if this helps you out or not, but U160 drives have a 
160Meg/sec bus, not the ability to stream data at 160Megs/sec

Thanks,

Josh Paetzel