MFC of "Large set of CAM improvements" breaks I/O to Adaptec 29160 SCSI controller

[Alexander Motin]

Pete French wrote:
>> Thanks. First step successful - I can steadily reproduce problem on
>> CURRENT. raidtest with 200 I/O streams over gmirror of two disks on same
>> channel triggers issue in seconds. Any I/O on channel dying after both
>> disks report "Queue full" error same time. The rest of system works
>> fine. If I preliminarily manually adjust queue depth of one disk -
>> everything works fine. I'll investigate it tomorrow.
> 
> Glad you have managed to dupliate it - the queue depth thing is
> inetersting, what changes did you make ? I can try them here and see
> if they improve the situation on either of my two machines.

camcontrol tags da0 -N 50

-- 
Alexander Motin