Setting 'max_queue' options for sx8.ko increases RAID5 recovery speed to ~23 MB/sec

Unload sx8 module. Add
options sx8 max_queue=24
to /etc/modules.conf and reload sx8. Now the recovery speed with a single adaptor and 8 drives is increased to 23000K/sec.

The effect of max_queue=32 has not much difference but in the comment of sx8.c version 1.0 it is claimed that problems seem to occur when the value exceeds ~30.

Thanks to Jeff Garzik's ultra-prompt reply in five minutes.