[CentOS] Adding RAM

Matt wrote:
> Cpu0  :  5.3% us,  4.0% sy,  0.0% ni, 81.5% id,  9.3% wa,  0.0% hi,  0.0% si
> Cpu1  : 11.3% us,  8.3% sy,  0.0% ni,  1.7% id, 78.1% wa,  0.7% hi,  0.0% si
> Mem:   8309188k total,  4761352k used,  3547836k free,   451464k buffers
> Swap:  2031608k total,      192k used,  2031416k free,  1564316k cached

If this is typical, you don't need more RAM...
cpu1 is waiting a lot, I/O bottleneck?