Atop, when you need to know exactly what's happening at the system-resource level

http://ift.tt/eA8V8J

You never seem to have enough RAM, CPU threads, or disk I/O. High level tools like top , htop , sar , iostat , or vmstat ... levels, as well as seeing resource consumption for each thread within a process of a multi-processor program.

from Google Alert - CPU processor http://ift.tt/1HujkxR
via IFTTT