On Tue, Oct 04, 2005 at 02:42:58PM +0000, Molle Bestefich wrote:

Andy Smith wrote:

quoted

I tried simply doing a

        dd if=/dev/sd[abcd] of=/dev/null

To check each disk in a very unsubtle fashion, but it drives the
load average on the machine way way up (like to 20+)

Checked that the disks are using DMA transfers (use 'hdparm')?

$ sudo hdparm /dev/sda

/dev/sda:
 HDIO_GET_MULTCOUNT failed: Inappropriate ioctl for device
 IO_support   =  0 (default 16-bit)
 readonly     =  0 (off)
 readahead    = 256 (on)
 geometry     = 14946/255/63, sectors = 122942324736, start = 0
$ sudo hdparm -d /dev/sda

/dev/sda:

Well that doesn't look right.

From dmesg:

ata1: SATA max UDMA/133 cmd 0x9E0 ctl 0xBE2 bmdma 0xDB00 irq 11
ata2: SATA max UDMA/133 cmd 0x960 ctl 0xB62 bmdma 0xDB08 irq 11
ata1: dev 0 cfg 49:2f00 82:7c6b 83:7b09 84:4003 85:7c69 86:3a01 87:4003 88:407f
ata1: dev 0 ATA, max UDMA/133, 240121728 sectors:
ata1: dev 0 configured for UDMA/133
ata2: dev 0 cfg 49:2f00 82:7c6b 83:7b09 84:4003 85:7c69 86:3a01 87:4003 88:407f
ata2: dev 0 ATA, max UDMA/133, 240121728 sectors:
ata2: dev 0 configured for UDMA/133
  Vendor: ATA       Model: Maxtor 6Y120M0    Rev: YAR5
  Type:   Direct-Access                      ANSI SCSI revision: 05
SCSI device sda: 240121728 512-byte hdwr sectors (122942 MB)
SCSI device sda: drive cache: write back
SCSI device sda: 240121728 512-byte hdwr sectors (122942 MB)
SCSI device sda: drive cache: write back
 sda: sda1 sda2 sda3
Attached scsi disk sda at scsi0, channel 0, id 0, lun 0
Attached scsi generic sg0 at scsi0, channel 0, id 0, lun 0,  type 0
  Vendor: ATA       Model: Maxtor 6Y120M0    Rev: YAR5
  Type:   Direct-Access                      ANSI SCSI revision: 05
SCSI device sdb: 240121728 512-byte hdwr sectors (122942 MB)
SCSI device sdb: drive cache: write back
SCSI device sdb: 240121728 512-byte hdwr sectors (122942 MB)
SCSI device sdb: drive cache: write back
 sdb: sdb1 sdb2 sdb3
Attached scsi disk sdb at scsi1, channel 0, id 0, lun 0
Attached scsi generic sg1 at scsi1, channel 0, id 0, lun 0,  type 0
ata3: SATA max UDMA/133 cmd 0x9F0 ctl 0xBF2 bmdma 0xE100 irq 10
ata4: SATA max UDMA/133 cmd 0x970 ctl 0xB72 bmdma 0xE108 irq 10
ata3: dev 0 cfg 49:2f00 82:7c6b 83:7b09 84:4003 85:7c69 86:3a01 87:4003 88:407f
ata3: dev 0 ATA, max UDMA/133, 240121728 sectors:
ata3: dev 0 configured for UDMA/133
ata4: dev 0 cfg 49:2f00 82:7c6b 83:7b09 84:4003 85:7c69 86:3a01 87:4003 88:407f
ata4: dev 0 ATA, max UDMA/133, 240121728 sectors:
ata4: dev 0 configured for UDMA/133
  Vendor: ATA       Model: Maxtor 6Y120M0    Rev: YAR5
  Type:   Direct-Access                      ANSI SCSI revision: 05
SCSI device sdc: 240121728 512-byte hdwr sectors (122942 MB)
SCSI device sdc: drive cache: write back
SCSI device sdc: 240121728 512-byte hdwr sectors (122942 MB)
SCSI device sdc: drive cache: write back
 sdc: sdc1 sdc2 sdc3
Attached scsi disk sdc at scsi2, channel 0, id 0, lun 0
Attached scsi generic sg2 at scsi2, channel 0, id 0, lun 0,  type 0
  Vendor: ATA       Model: Maxtor 6Y120M0    Rev: YAR5
  Type:   Direct-Access                      ANSI SCSI revision: 05
SCSI device sdd: 240121728 512-byte hdwr sectors (122942 MB)
SCSI device sdd: drive cache: write back
SCSI device sdd: 240121728 512-byte hdwr sectors (122942 MB)
SCSI device sdd: drive cache: write back
 sdd: sdd1 sdd2 sdd3
Attached scsi disk sdd at scsi3, channel 0, id 0, lun 0
Attached scsi generic sg3 at scsi3, channel 0, id 0, lun 0,  type 0