> Jack, > > I think the apparent degradation was the result of profiling flags in > the .config file. > > I turned off TASKSTATS, AUDIT, OPTIMIZE_FOR_SIZE, PROFILING (including > OPROFILE), and GCOV_KERNEL. > > Somewhere in there I got the performance back. > > Without intending to run any of the tools at the time of my tests, I > did not expect the consequences (I would only expect that if I was > using a tool). > > Apologies for any confusion I passed to others. > > > David > [Jack Wang] Nice to hear that. > > > On Tue, Jul 12, 2011 at 12:34 PM, ersatz splatt <ersatzsplatt@xxxxxxxxx> wrote: > > 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 -- 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
