Jack, fio script is: [global] rw=read direct=1 time_based runtime=1m ioengine=libaio iodepth=32 bs=512 [dB] filename=/dev/sdb cpus_allowed=2 [dC] filename=/dev/sdc cpus_allowed=3 [dD] filename=/dev/sdd cpus_allowed=4 [dE] filename=/dev/sde cpus_allowed=5 (keep in mind this is a system with several cores) Before running the script I (of course) shut down coalescing: echo "2"> /sys/block/sdb/queue/nomerges echo "2"> /sys/block/sdc/queue/nomerges echo "2"> /sys/block/sdd/queue/nomerges echo "2"> /sys/block/sde/queue/nomerges echo noop > /sys/block/sdb/queue/scheduler echo noop > /sys/block/sdc/queue/scheduler echo noop > /sys/block/sdd/queue/scheduler echo noop > /sys/block/sde/queue/scheduler As you know, disk details are shown in the log on driver load: pm8001 0000:05:00.0: pm8001: driver version 0.1.36 pm8001 0000:05:00.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16 scsi4 : pm8001 scsi 4:0:0:0: Direct-Access SEAGATE ST9146803SS 0004 PQ: 0 ANSI: 5 sd 4:0:0:0: [sdb] 286749488 512-byte logical blocks: (146 GB/136 GiB) sd 4:0:0:0: Attached scsi generic sg1 type 0 sd 4:0:0:0: [sdb] Write Protect is off sd 4:0:0:0: [sdb] Write cache: enabled, read cache: enabled, supports DPO and FUA sdb: unknown partition table sd 4:0:0:0: [sdb] Attached SCSI disk scsi 4:0:1:0: Direct-Access SEAGATE ST9146803SS 0006 PQ: 0 ANSI: 5 sd 4:0:1:0: Attached scsi generic sg2 type 0 sd 4:0:1:0: [sdc] 286749488 512-byte logical blocks: (146 GB/136 GiB) sd 4:0:1:0: [sdc] Write Protect is off sd 4:0:1:0: [sdc] Write cache: enabled, read cache: enabled, supports DPO and FUA sdc: unknown partition table sd 4:0:1:0: [sdc] Attached SCSI disk scsi 4:0:2:0: Direct-Access SEAGATE ST9146803SS 0004 PQ: 0 ANSI: 5 sd 4:0:2:0: [sdd] 286749488 512-byte logical blocks: (146 GB/136 GiB) sd 4:0:2:0: Attached scsi generic sg3 type 0 sd 4:0:2:0: [sdd] Write Protect is off sd 4:0:2:0: [sdd] Write cache: enabled, read cache: enabled, supports DPO and FUA sdd: unknown partition table sd 4:0:2:0: [sdd] Attached SCSI disk scsi 4:0:3:0: Direct-Access SEAGATE ST9146803SS 0004 PQ: 0 ANSI: 5 sd 4:0:3:0: [sde] 286749488 512-byte logical blocks: (146 GB/136 GiB) sd 4:0:3:0: Attached scsi generic sg4 type 0 sd 4:0:3:0: [sde] Write Protect is off sd 4:0:3:0: [sde] Write cache: enabled, read cache: enabled, supports DPO and FUA sde: unknown partition table sd 4:0:3:0: [sde] Attached SCSI disk The firmware version is 1.11. Let me know if you have any other questions. Please let me know if you can confirm the performance degradation with the driver as it is. David On Mon, Jul 11, 2011 at 9:18 PM, Jack Wang <jack_wang@xxxxxxxxx> wrote: > Could you share your fio test scripts? disk detail and HBA firmware version > are also wanted if available. > > Jack >> >> I have one HBA connected directly to 4 SAS drives ... using a single 1 >> to four cable. >> >> >> On Mon, Jul 11, 2011 at 6:27 PM, Jack Wang <jack_wang@xxxxxxxxx> wrote: >> >> Hello Jack Wang and Lindar Liu, >> >> >> >> >> >> I am running the pm8001 driver (on applicable hardware including a >> >> several core SMP server). >> >> >> >> When I run on an older kernel -- e.g. 2.6.34.7 -- I get about 73Kiops >> >> via an fio test. >> >> >> >> When I run a current kernel -- e.g. 2.6.39.2 -- on the same system and >> >> same storage I get about 15Kiops running the same fio test. >> >> >> >> Perhaps something has changes in the kernel that is not being accounted >> > for? >> >> Are you two still maintaining this driver? >> >> >> >> >> >> Regards, >> >> David >> > [Jack Wang] Could you give your detailed topology, I will later try to >> > investigate the performance issue, but as I remember an Intel developer >> > reports in mailist some changes in block layer lead to JBOD performance >> > degradation. >> > >> > >> -- >> To unsubscribe from this list: 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 > > -- To unsubscribe from this list: 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
