Re: [OT] RAID controllers blocking one another?

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On Fri, 18 Jan 2008 16:54:17 +0100
Hannes Dorbath <light@theendofthetunnel.de> wrote:

> Sean Davis wrote:
> > 150-200MB/s writing and somewhat faster for reading
> 
> That actually seems dead slow. Whatever RAID level you configured,
> there is no sane way for it to be that slow. Is this a RAID 5/6
> array? Did you forgot to align your file system to stripe boundaries?

That seem that slow for SATA on a write. Assuming 20 (on each
controller) disks random write I would guess the best you could pull off
would be about 200 Megs a second. That's on a good day.

So 200MBs per controllers isn't that out of bounds. I would agree that
seems slow for reads though.

And to answer the question, no I have not seen the behavior he is
experiencing but to be honest I would never run that many sata drives.
I would have long pushed to SAS on that scale.

Sincerely,

Joshua D. Drake




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