Package: procmeter (2.4b-4)

X based performance meter, like xload, but more options

ProcMeter displays constantly updating graphs of system information. Many different graphs are supported, including:

 Total cpu usage, cpu used by user, niced, or system processes, cpu idle
 time, load average, number of context switches, number of processes. Amount
 of swapping, paging, swap in, page in, swap out, page out. Amount of disk
 accesses, reads, writes, or interrupts. MB of free, used, buffer, or cached
 memory. Amount of swap space used. Number of packets received or transmitted
 over local interfaces, ethernet, or slip/ppp. Number of collisions on
 ethernet, battery life stats.

As if all that wasn't enough, procmeter also allows you to write programs that communicate with procmeter and add new graphs to the display.

Procmeter can also log statistics to a file, and play it back later.