I believe the software only runs on 1 processor, so if you have a Hyperthreading processor (some Pentium 4's have this), it will only run on one of the 2 virtual processors. Do you have a P4?

Hi xenon civic coupe

You may want to click on this thread

http://www.worldcommunitygrid.org/forums/wcg/viewthread?thread=1054

and this thread

http://www.worldcommunitygrid.org/forums/wcg/viewthread?thread=484

Regards

Please understand. The program is not at fault.

Your computer is not at fault.

There is no fault.

The program is using all it can and the computer is running as fast as it can.

The only problem is the way that the operating system reports the utilization to you (and everyone else of course). It reports it in such a way that makes you believe that you are not running full speed but you are. This only happens with HT processors.

Kind Regards

ok. :)

i guess i didn't understand it very wel.
the strange point is that other programs like WCG make my processor show the 100% on the task manager screen.

that makes me confused.....

but ok. sorry for the misunderstanding. :)

PS: this is the page showing the other program i used......
http://bertjah.kicks-ass.net:81/rc5/byhost.html

Greetz,
Marko

Don't worry about it. Hyperthreading confuses a lot of people. Welcome to Intel marketing spin On a serious note, simultaneous multi-threading (SMT) has been around a while (SMT is the generic name while HyperThreading is Intel's brandname for it).

Here's how it works in a nutshell:
Intel added some logic to its CPUs so that they can manage running two threads at the same time. They do this by injecting thread #2's instructions between the gaps in thread #1's pipeline. Intel processors are notorious for having very long pipelines. Some CPU instructions take several clock cycles to perform. These cause gaps in the pipeline. Gaps essentially waste CPU cycles. So what Intel did is put SMT on their chips to inject another thread's instructions into these gaps, thereby improving efficiency.

The problem is how do you get two threads to even run at the same time? The scheduler is in the operating system. On a true SMP system, the OS knows it has 2 or more processors and runs a thread on each processor. But HT processors are just a single CPU, so normally the OS will just run 1 thread at any given time. How do you take advantage of the HT technology? The Intel chip tricks the OS into thinking there are two CPUs. Thus, the OS attempts to schedule 2 threads at the same time on a single CPU. That's also why the Task Manager shows 2 CPUs. It's also why you see 50% utilization being reported when in fact it's really 100%.

HT improves the performance just a little by squeezing in a few more instructions when normally there would be wasted CPU cycles. Of course, if there's nothing else to run, they're wasted anyway. Thus the best improvement you're liley see with HT turned on is maybe 10% - 20%. On the flip side, HT can slow things down by "thrashing" the CPU and cache. Certain types of programs lend themselves to easily benefit from HT, while some take a performance hit. That's why you'll see some benchmarks run really well on HT and sometimes they run really slow (relatively speaking).