CAM//SCSI disk timeouts

[Julian Elischer]

If we are talkign to a raid array and it discovers that it has to
do some maintanance (e.g. declare a physical disk bad or recreate
some data on the fly) it is possible that transactions to the raid
that are outstanding may tak a lot longer than usual. In particular,
we've seen the case where a log entry in teh Raid controller's log
that indicates that a drive has been declared bad, is often accompanied
in FreeBSD with a set of CAM /scsi-disk timeouts
and things degrade from there...

Where can I find the  timeouts in force fo rscsi disks and teh retry policies?

I need to compare the theoretical behaviour of FreeBSD CAM with the 
theoretical timeouts needed for the raid array, given a disk failure..