Very slow I/O performance on HP BL465c

[Nathan Le Nevez]

Hi,

I'm running 7.2-p3 on 2x HP BL465c blade servers, one of which performs very
poorly. Both have the same RAID controller and 2 x 146GB 10k SAS disks
configured in RAID-1. Both controllers have write-cache enabled. Both
servers are running the same BIOS and firmware versions. Neither servers are
running any services other than sshd.

Blade with good performance (2 x Opteron 2218, 8GB RAM):

ciss0: <HP Smart Array E200i> port 0x4000-0x40ff mem
0xfdf80000-0xfdffffff,0xfdf70000-0xfdf77fff irq 19 at device 8.0 on pci80
ciss0: [ITHREAD]
da0 at ciss0 bus 0 target 0 lun 0
da0: <COMPAQ RAID 1  VOLUMES MOPK:>  AFPi xCePdU  D#i2r Leacuntc hAcecde!s
s SCSI-5 device
da0: 135.168MB/s transfers
dSaM0P::  CAoP CPU #3 Launched!
mmand Queueing Enabled
da0: 139979MB (286677120 512 byte sectors: 255H 32S/T 35132C)

Blade with bad performance (2 x Opteron 2352, 16GB RAM):

ciss0: <HP Smart Array E200i> port 0x4000-0x40ff mem
0xfdf80000-0xfdffffff,0xfdf70000-0xfdf77fff irq 19 at device 8.0 on pci80
ciss0: [ITHREAD]
da0 at ciss0 bus 0 target 0 lun 0
da0: <COMPAQ RAID 1  VOLUME OK> Fixed Direct Access SCSI-5 device
da0: 135.168MB/s transfers
da0: Command Queueing Enabled
da0: 139979MB (286677120 512 byte sectors: 255H 32S/T 35132C)

# dbench -t 10  1              2              3             4
blade1          183.456 MB/sec 236.86 MB/sec  299.28 MB/sec  192.675 MB/sec
blade2          6.97931 MB/sec 9.42293 MB/sec 10.2482 MB/sec 12.407 MB/sec

Any help/ideas would be greatly appreciated. I have run through all the
Insight diagnostics tools and it fails to find anything wrong with the slow
server.

Cheers,
Nathan