mpt request timed out

[Ståle Kristoffersen]

Hi, I'm not sure if this is the right list, please tell me if it is.

I'm having problems with mpt timeouts when putting load on the disks
connected to it.
I have the mpt-adapter connected to a sas-expander, and several disks
connected to that expander:

mpt0: <LSILogic SAS/SATA Adapter> port 0xc800-0xc8ff mem
0xfe8fc000-0xfe8fffff,0xfe8e0000-0xfe8effff irq 16 at device 0.0 on pci1
mpt0: [ITHREAD]
mpt0: MPI Version=1.5.20.0

ses0 at mpt0 bus 0 scbus0 target 0 lun 0
ses0: <LSILOGIC SASX36 A.1 7015> Fixed Enclosure Services SCSI-3 device
ses0: 300.000MB/s transfers
ses0: Command Queueing enabled
ses0: SCSI-3 SES Device

And all the disks are consumer-grade SATA-diskes like this:
da0 at mpt0 bus 0 scbus0 target 1 lun 0
da0: <ATA ST31000528AS CC38> Fixed Direct Access SCSI-5 device
da0: 300.000MB/s transfers
da0: Command Queueing enabled
da0: 953869MB (1953525168 512 byte sectors: 255H 63S/T 121601C)

The error I'm seeing is this:
http://folk.uio.no/stalk/mpt/timeout.txt

I've also put out a full dmesg from boot:
http://folk.uio.no/stalk/mpt/dmesg.txt
(i've since added 4 new disks, but the error was there before that).

What can be causing these timeouts? The controller resets everything and
zfs is not complaining:

  pool: media
 state: ONLINE
 scrub: scrub stopped after 0h4m with 0 errors on Wed May 12 13:58:05 2010
config:

        NAME        STATE     READ WRITE CKSUM
        media       ONLINE       0     0     0
          raidz1    ONLINE       0     0     0
            da14    ONLINE       0     0     0
            da11    ONLINE       0     0     0
            da6     ONLINE       0     0     0
            da3     ONLINE       0     0     0
          raidz1    ONLINE       0     0     0
            da15    ONLINE       0     0     0
            da12    ONLINE       0     0     0
            da9     ONLINE       0     0     0
            da5     ONLINE       0     0     0
          raidz1    ONLINE       0     0     0
            da8     ONLINE       0     0     0
            da2     ONLINE       0     0     0
            da0     ONLINE       0     0     0
            da4     ONLINE       0     0     0
          raidz1    ONLINE       0     0     0
            da1     ONLINE       0     0     0
            da13    ONLINE       0     0     0
            da10    ONLINE       0     0     0
            da7     ONLINE       0     0     0
          raidz1    ONLINE       0     0     0
            da17    ONLINE       0     0     0
            da18    ONLINE       0     0     0
            da19    ONLINE       0     0     0
            da20    ONLINE       0     0     0

errors: No known data errors

but clients time out or gets an error if they try to do IO while the
connection is down, and thats causing havoc. The timeouts last from 10 up
to 30 seconds each. 

I'd appreciate any ideas!

-- 
Ståle Kristoffersen