Linux troubleshooting steps

1) Are the CPUs overtaxed?
2) Are one or more processes using most of the CPU power?
3) Is swap space usage increasing?
5) Is the system spending time waiting for I/O?
6) Is the system writing or reading from disk too often?
7) Is the system saturating the network card?
8) Is a process using too much RAM? (Is its Resident Set Size increasing over time?)
9) What type of memory is a process using? (cat /proc//status)
10) Is the process stack size increasing? (VmStk)
11) Is shared memory use increasing?