2007/9/18, SpringFlowers AutumnMoon <summercoolness / gmail.com>:
> I tested some computation intensive Ruby code.  When running, the CPU
> usage on the machines are no where near 100%.  One is an Intel Hyper
> Threading machine.  One is an Intel Core 2 Duo.
>
> on the Hyper Threading machine, the CPU usage went up from 10% both to
> 70% for one and 30% for the other...
>
> on the Core 2 Duo, the CPU usage went from 20% both to about 70% for
> both CPU core.
>
> I guess both CPUs know how to distrubute the calculations among two
> cores or two virtual cores?   But the question is, why not both near
> 100%?  Why allow some slack for CPU idle time?
>
> but then again, if I run a similar program using Python, it is the same
> thing.  I tried and set the process priority of the programs to the
> highest and nothing changed.

Maybe your process is IO bound - probably without you being aware of
it (e.g. through paging, network IO, IPC or such).

robert