On Monday 17 January 2005 16:51, Andy Smith wrote:

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.

I edited out the "inappropriate ioctl" warnings in my output. Since the drives 
are not partitions, a flush would indeed be inappropriate. hdparm -t only 
does read timings anyway. As to why your md0 output is strange - no idea I'm  
afraid. :(

Andrew Walrond