3ware 8506 JBOD problem

[Scott T. Smith]

I'm running FreeBSD 5.2.1-RELEASE on a machine with three 3ware 8506-8
cards, each with 8 disks attached in JBOD mode.  I'm having problems
making hotswapping work properly, and I'm wondering if anyone else has
seen the same thing, and if it's a controller or OS problem.

If I issue consecutive reads from two disks on the same controller, and
yank a disk, then the process reading from that disk hangs (obviously)
while the other keeps going.  However, about 20 seconds later, the other
process hangs for a bit too.

Then if I issue the 'maint remove c2 u0' command, the other disk will
hang again.

This seems like odd behaviour for a RAID card.  Is it just that you
cannot remove a disk without telling the controller first?  Or does JBOD
mode behave less effectively than RAID mode?

	Scott