how to "find which process hurted my processor"

[sathiya]

1. In a server, several users are allowed to login, and run processes.

By using uptime i can see the load average, if is high then i can see the top, and find which user's process is making the problem.

But how do i do the same which happened earlier.

Say i am not able to monitor a issue lively, i came to back to monitor that after 1 hour.. How can i find... which process, which user made that issue ??

Hence it had crossed an hour, i cannot use the top, uptime.. is there any other way..

2. And one more thing, if because of any process if the server gots hang, and i am forced to reboot, how can i find which process made the server to hang ??

[smolloy]

Nagios might be what you're looking for.