Hi
Have a look
dd if=/dev/zero of=${ 1} megs bs=10000000 count=$1
try passing different values for $1 and it will create file of different sizes
The value, 2000, is passed to the script and the dd command creates a file called 2000megs with 100 blocks, each 1MB in size, of buffered zeros
you could prefix a tiem in front of it to get the timing information like
time dd if=/dev/zero of=${ 1} megs bs=10000000 count=$1
regards
Hrishy