Maximum performance for caching

[Roy Sigurd Karlsbakk]

>> ps axf
>> or just man ps
>
> Ok. I have checked this. Almost all of the TUX processes are in S 
> state.
> <snip/>
> But still my load average is about 2. What does this mean? This machine
> is dedicated to TUX server btw. The traffic is pretty huge, about 4
> million pageview / day. 1 page has about 10 images, so it is about 40
> million access to the images.

ps ax | grep -w '[DRZ]'
that will show you all processes running, in D state (waiting for I/O) 
and zombies

perhaps that'll help you out