On Wed, Mar 13, 2013 at 09:36:07PM -0400, Thor Lancelot Simon wrote: > 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.
Actually, I think the simplest correct answer is that it should be the minimum number of openings presented by any individual underlying component. I cannot see any good reason why it should be either more nor less than that value. Thor
