sar tool

[Matt Roth]

iostat may provide the information you're looking for.

NAME
       iostat - Report Central Processing Unit (CPU) statistics and 
input/output statistics for devices and partitions.

SYNOPSIS
       iostat [ -c | -d ] [ -k ] [ -t ] [ -V ] [ -x ] [ { device [  ...  
] | ALL } ] [ -p [ { device | ALL } ] ] [ interval [ count ] ]

Matthew Roth
InterMedia Marketing Solutions
Software Engineer and Systems Developer