Re: FIXED: mpt Serious performance issues

[Thor Lancelot Simon <tls%panix.com@localhost>]

On Wed, Feb 09, 2011 at 09:38:02AM -0700, Michael L. Hitch wrote:
> 
>   This might be the "adapt->adapt_max_periph = maxq" setting in
> mpt_netbsd.c, if maxq is > 256.  The tagging done in the scsipi
> layer can only deal with 256 tags.  I'm not sure how that would
> affect the mpt(4) driver.  I did some work to get ciss(4) to do
> tagged queueing, and as best I could understand tagged queuing and

But ciss uses ld(4), doesn't it?  It's not a SCSI adapter?

There should be no harm to supporting less tags than the maximum for
FibreChannel -- we just won't use all the potential queueing resources
of the device.  If there's an issue with FC or SAS targets I suspect it
is something different.

Thor