How can the read/write speed of a partition or drive be measured?

Question

How can I preferable from the terminal measure the read and write speeds of /dev/sdx?

Answer 1

The easiest way is to use this command:

hdparm

Typical usage and output:

# hdparm -tT /dev/sda1
/dev/sda1:
 Timing cached reads:   2408 MB in  2.00 seconds = 1201.84 MB/sec
 Timing buffered disk reads: 260 MB in  3.03 seconds =  85.95 MB/sec

Please be careful with this command and don't play with switches too much unless you know what you are doing as some of them might even kill your drive if not correctly used.