Some useful unix commands i came across today

vmstat [pamam1] [param2]

shows the server statics along with swap space, cache,io and cpu utilization.

this stats are shown [param2] number of times with [param1] duration in between.

top

this command also shows the server statistics in detail with
contribution from each process.
This also shows the memory used,cpu utilization and command used for each thread.

finger

Shows the user who are currently logged into the node.