Mr O wrote:

> I want to benchmark my read speeds on my cdrom's. How?

time dd if=/dev/cdrom of=/dev/null bs=<a multiple of 2048>

multiply records by block size for bytes transferred.
divide bytes by seconds for bytes/second.
divide by 1024 or 1048576 for kbytes or mbytes/second.

Try different block sizes for fun.

Eject and reinsert the disk to avoid the buffer cache.

BTW, CD-ROMs have different speeds on different parts of the disk.
They're neither CAV nor CLV.  (CAV is Constant Angular Velocity - the
disc spins at a fixed speed.  CLV is ...Linear... - the disc moves
past the laser at a fixed speed.)

You can use dd's count=<number> parameter to read only the first part
of the disc.

-- 
Bob Miller                              K<bob>
kbobsoft software consulting
http://kbobsoft.com                     [EMAIL PROTECTED]

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