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

[Scott Long]

On Apr 29, 2010, at 7:47 AM, Robert Noland wrote:
> 
> 
> Scott Long wrote:
>> On Apr 29, 2010, at 2:50 AM, 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.
>>> 
>> For the record, queue-full is a common, expected condition in CAM.  It's not something that should be avoided =-)
> 
> Should we maybe have a counter in sysctl rather than flooding the console with these messages then?

That's a pretty good idea.  I'll make it happen.

Scott