scrub is very slow

[joseangel]

[root@storsv1] /root
[5 - 8:52] # date
Fri Feb 25 08:52:25 CET 2011

[root@storsv1] /root
[6 - 8:52] # zpool status
pool: jbodpool
state: ONLINE
scan: scrub in progress since Thu Feb 24 15:34:04 2011
598G scanned out of 1.72T at 9.83M/s, 33h37m to go
0 repaired, 33.98% done
config:

    NAME        STATE     READ WRITE CKSUM
    jbodpool    ONLINE       0     0     0
      sdb1      ONLINE       0     0     0
      sdc1      ONLINE       0     0     0
      sdd1      ONLINE       0     0     0
      sde1      ONLINE       0     0     0

errors: No known data errors

[root@storsv1] /root
[7 - 8:52] # uname -a
Linux storsv1 2.6.32-28-server #55-Ubuntu SMP Mon Jan 10 23:57:16 UTC 2011 x86_64 GNU/Linux

[ 1.472531] ata3: SATA link down (SStatus 0 SControl 300)
[ 1.472694] ata7: SATA link up 1.5 Gbps (SStatus 113 SControl 310)
[ 1.540937] ata7.00: ATA-7: WDC WD5000AAKS-00TMA0, 12.01C01, max UDMA/133
[ 1.541051] ata7.00: 976773168 sectors, multi 16: LBA48 NCQ (depth 0/32)
[ 1.580511] ata7.00: configured for UDMA/100
[ 1.970032] ata4: SATA link down (SStatus 0 SControl 300)
[ 2.320033] ata5: SATA link down (SStatus 0 SControl 300)
[ 2.670025] ata6: SATA link down (SStatus 0 SControl 300)
[ 2.670251] scsi 2:0:0:0: Direct-Access ATA WDC WD5000AAKS-0 12.0 PQ: 0 ANSI: 5
[ 2.670614] sd 2:0:0:0: Attached scsi generic sg2 type 0
[ 2.670691] sd 2:0:0:0: [sdb] 976773168 512-byte logical blocks: (500 GB/465 GiB)
[ 2.670747] sd 2:0:0:0: [sdb] Write Protect is off
[ 2.670750] sd 2:0:0:0: [sdb] Mode Sense: 00 3a 00 00
[ 2.670778] sd 2:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[ 2.670939] sdb: sdb1 sdb9
[ 2.705296] sd 2:0:0:0: [sdb] Attached SCSI disk
[ 3.020075] ata8: SATA link up 1.5 Gbps (SStatus 113 SControl 310)
[ 3.068710] ata8.00: ATA-7: WDC WD5000AAKS-00TMA0, 12.01C01, max UDMA/133
[ 3.068826] ata8.00: 976773168 sectors, multi 16: LBA48 NCQ (depth 0/32)
[ 3.100511] ata8.00: configured for UDMA/100
[ 3.100690] scsi 5:0:0:0: Direct-Access ATA WDC WD5000AAKS-0 12.0 PQ: 0 ANSI: 5
[ 3.100993] sd 5:0:0:0: [sdc] 976773168 512-byte logical blocks: (500 GB/465 GiB)
[ 3.101016] sd 5:0:0:0: Attached scsi generic sg3 type 0
[ 3.101303] sd 5:0:0:0: [sdc] Write Protect is off
[ 3.101406] sd 5:0:0:0: [sdc] Mode Sense: 00 3a 00 00
[ 3.101433] sd 5:0:0:0: [sdc] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[ 3.101736] sdc: sdc1 sdc9
[ 3.145355] sd 5:0:0:0: [sdc] Attached SCSI disk
[ 3.450057] ata9: SATA link up 1.5 Gbps (SStatus 113 SControl 310)
[ 3.477673] ata9.00: ATA-7: WDC WD5000AAKS-00TMA0, 12.01C01, max UDMA/133
[ 3.477789] ata9.00: 976773168 sectors, multi 16: LBA48 NCQ (depth 0/32)
[ 3.510748] ata9.00: configured for UDMA/100
[ 3.510912] scsi 7:0:0:0: Direct-Access ATA WDC WD5000AAKS-0 12.0 PQ: 0 ANSI: 5
[ 3.511186] sd 7:0:0:0: [sdd] 976773168 512-byte logical blocks: (500 GB/465 GiB)
[ 3.511197] sd 7:0:0:0: Attached scsi generic sg4 type 0
[ 3.511514] sd 7:0:0:0: [sdd] Write Protect is off
[ 3.511618] sd 7:0:0:0: [sdd] Mode Sense: 00 3a 00 00
[ 3.511644] sd 7:0:0:0: [sdd] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[ 3.511935] sdd: sdd1 sdd9
[ 3.555531] sd 7:0:0:0: [sdd] Attached SCSI disk
[ 3.860052] ata10: SATA link up 1.5 Gbps (SStatus 113 SControl 310)
[ 3.891655] ata10.00: ATA-7: WDC WD5000AAKS-00TMA0, 12.01C01, max UDMA/133
[ 3.891772] ata10.00: 976773168 sectors, multi 16: LBA48 NCQ (depth 0/32)
[ 3.930945] ata10.00: configured for UDMA/100
[ 3.931126] scsi 9:0:0:0: Direct-Access ATA WDC WD5000AAKS-0 12.0 PQ: 0 ANSI: 5
[ 3.931412] sd 9:0:0:0: [sde] 976773168 512-byte logical blocks: (500 GB/465 GiB)
[ 3.931437] sd 9:0:0:0: Attached scsi generic sg5 type 0
[ 3.931716] sd 9:0:0:0: [sde] Write Protect is off
[ 3.931823] sd 9:0:0:0: [sde] Mode Sense: 00 3a 00 00
[ 3.931848] sd 9:0:0:0: [sde] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[ 3.932145] sde: sde1 sde9
[ 3.965257] sd 9:0:0:0: [sde] Attached SCSI disk