Hi, I have a server with a: SCSI storage controller: Adaptec AHA-3960D / AIC-7899A U160/m (rev 01) Subsystem: Adaptec AHA-3960D U160/m connected to 14 Vendor: MAXTOR Model: ATLAS15K_36SCA Rev: DTA0 7 on each channel. On 2.6.12 a simple 'dd' write test gives 70 Meg/second: cage # time dd of=/dev/null if=/dev/sdl bs=1024k count=100 100+0 records in 100+0 records out 104857600 bytes transferred in 1.555210 seconds (67423431 bytes/sec) real 0m1.557s user 0m0.001s sys 0m0.770s On 2.6.13-rc1 the same test takes just short on 1 minute and reports slightly less than 2 M/Second. cage # time dd of=/dev/null if=/dev/sdl bs=1024k count=100 100+0 records in 100+0 records out 104857600 bytes transferred in 54.576592 seconds (1921293 bytes/sec) real 0m54.578s user 0m0.000s sys 0m0.360s I'm happy to try patches or perform other tests. NeilBrown - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html