If you are in charge of a garden-variety Linux system, you’ll probably like nmon. It is a performance monitoring tool that combines statistics for the core kernel objects. You can see process list (similar to top), memory, network, block I/O and many other statistics, all in nice ncurses-based environment.
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Tags: Linux, performance monitoring

Does garden-variety include ubuntu. If not then this htop is also a great improvement on top.
see http://blog.andrewbeacock.com/2007/12/htop-great-alternative-to-top-for.html
Yes, I tried it on 64bit 9.04 and it works as expected. The file output for nmon_x86_64_ubuntu810 says:
nmon_x86_64_ubuntu810: ELF 64-bit LSB executable, \
x86-64, version 1 (SYSV), dynamically linked (uses shared libs), \
for GNU/Linux 2.6.8, not stripped
As long as you have
ncursesinstalled, you should be OK.