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Re: Where is the component queue depth actually used in the raidframe system?

On Wed, Mar 13, 2013 at 03:32:02PM -0700, Brian Buhrow wrote:
>       hello.   What I'm seeing is that the underlying disks under both a
> raid1 set and a raid5 set are not seeing anymore than 8 active requests at
> once across the entire bus of disks.  This leaves a lot of disk bandwidth
> unused, not to mention less than stellar disk performance.  I see that
> RAIDOUTSTANDING is defined as 6 if not otherwise defined, and this suggests
> that this is the limiting factor, rather than the actual number of requests
> allowed to be sent to a component's queue.

It should be the sum of the number of openings on the underlying components,
divided by the number of data disks in the set.  Well, roughly.  Getting it
just right is a little harder than that, but I think it's obvious how.


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