Queue full event with LSI Logic SAS/SATA Adapter on FreeBSD 7.2

I ran into this trouble while installing FreeBSD 7.2 to IBM IntelliStation Z Pro that within LSI SAS/SATA adapter (mpt0)...

mpt0: port 0x2000-0x20ff mem 0xfd210000-0xfd213fff,0xfd200000-0xfd20ffff irq 16 at device 0.0 on pci1
mpt0: [ITHREAD]
mpt0: MPI Version=1.5.13.0
mpt0: Capabilities: ( RAID-0 RAID-1E RAID-1 )
mpt0: 0 Active Volumes (2 Max)
mpt0: 0 Hidden Drive Members (10 Max)

It will show following message repeat many times while disk accessing...

mpt0: QUEUE FULL EVENT: Bus 0x00 Target 0x00 Depth 128

It might not crash your system but still annoying though! The reason is the hard drive do not accept too much access in queue (That means it depends on hard drive factory setting)!

Okay, you can check its default setting with following commands...

# camcontrol tag da0
(pass0:mpt0:0:0:0): device openings: 255

You should set its tags lower than the error shows.

# camcontrol tag da0 -N 127
(pass0:mpt0:0:0:0): device openings: 127

After that, you can test it with find...

# cd /
# find . -name="sudo"

And track your log file

# tail -f /var/log/messages

You won't see annoying warnings anymore if the setting works, or you have to set again with lower depth value.

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