On Thu, Dec 28, 2000 at 03:59:05PM -0800, Matthew Jacob wrote:
> > 
> > SCSI disks typically can take a queue of 16-32, Fibre-Channel are usually
> > 64.  These are fixed-length queues, so if there are multiple initiators
> > they are shared between the initiators.
> > 
> > RAID boxes are usually broken:  64-256 tags, but these are shared
> > among all the LUNs, so if you have 64 commands outstanding on each
> > of LUNs 0..4, you have no tags available for LUN 5 if you ever want
> > to send it a command.  You can get a QFULL condition with no outstanding
> > commands in that case.
> > 
> > What Jim Kahn recommends it to run until you get QFULL, set that as
> > the limit, then after 1m clear the limit. 
> 
> Yeah, I recommended something like Jim's idea a while back- I think I said 30
> seconds. It adds a bit of hysteresis to Bob Snively's way of doing stuff.

Maybe we can just clear the limit when the number of commands in the running
queue is below a mark. This mean we need to account the number of
commands in the target's queue; and a way to dynamically set this limit.

--
Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
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