On Mon, Jan 17, 2005 at 04:24:47PM +0000, Andrew Walrond wrote:

FWIW I get these results with RAID-0

andrew@orac ~ $ sudo hdparm -t /dev/sda /dev/sdb /dev/md0

/dev/sda:
 Timing buffered disk reads:  170 MB in  3.00 seconds =  56.64 MB/sec

/dev/sdb:
 Timing buffered disk reads:  170 MB in  3.02 seconds =  56.37 MB/sec

/dev/md0:
 Timing buffered disk reads:  236 MB in  3.02 seconds =  78.08 MB/sec

As an aside, when I try this, how come I get this:

$ sudo hdparm -t /dev/sda /dev/sdb /dev/md0

/dev/sda:
 Timing buffered disk reads:  152 MB in  3.03 seconds =  50.19 MB/sec
HDIO_DRIVE_CMD(null) (wait for flush complete) failed: Inappropriate ioctl for device

/dev/sdb:
 Timing buffered disk reads:  152 MB in  3.03 seconds =  50.24 MB/sec
HDIO_DRIVE_CMD(null) (wait for flush complete) failed: Inappropriate ioctl for device

/dev/md0:
 Timing buffered disk reads:  read(2097152) returned 524288 bytes

(note warnings about ioctls and no speed output for /dev/md0)

These are SATA drives in a RAID 1.