system monitoring tool

[Costello]

Hello,
   I am in need of a public domain package which monitors and displays
information about the system while an application is running. The infor-
mation would include such things as CPU usage, memory usage, IO device
usage, etc. I would like to be able to start up this package along with
the application and have it periodically spit out the desired info.
Unix commands such as "ps" and "time" aren't informative enough (at least,
not as far as I can tell). I am running a Mac IIx with A/UX 2.0. I 
would really like some source code to such a monitor tool. Thanks for
any info. Please mail directly to me at: costello at mitre.org
Cheers! /Roger