Hyper Thread useless in real-world working?

Hi, my system is below in my signature. Basically I have an i7-2760QM 2,4Ghz-3,5Ghz. At 99% there are 4 processors active and the rest is at 0%. So today I wanted to see if I can get all processors somehow at 100% to see what kind of power Hyper Thread would actually offer me.

I ran 2x Virtualbox machines with each 4 cores assigned and 4GB RAM.
I extracted a 8GB .rar archive at the same time.

Results: for a short period all 8 processors were active with each ~50% usage. Then most of them went to 0% usage again. However, the startup of those virtual machines took ages altough the CPU usage was at ~10%-20% on 4 processors. I also tried this scenario with the "cores unparked" fix. Same results.

So actually you never really get all 8 processors to 100%.. even with 16GB of RAM I can't run enough virtual machines to do that? Additionally it doesn't even make sense as 2 virtual machines with 20% CPU usage are already slow as hell?

Why would I need Hyper Thread then?

Thanks :S

 

Keep the task monitor open long enough, and you'll see that cores fire up snd park all the time for various tasks. Hyper-threading does a lot of small load balancing.

 

If you run a multithreaded benchmark then you might see a 20% or so increase using hyper threading. It's only an incremental increase in speed, and in some cases you can even get higher performance by turning it off as you can turbo higher.

 

Ye disabling HT and having just 4 cores with each 3,4Ghz is nice.. But then I wouldn't need HT anyway?

Well.. I ran 2x virtual machines and only used all 8 processors for a few seconds.. also they weren't at a high usage.. still the virtual machines took ages to boot up. I waited with the Task monitor for like 2 mins.

 

Instead of extracting a RAR archive (which will also slow down your storage devices instead of simply loading your cpu cores), try running something that taxes the cpu exclusively - instead of also hammering on the storage sub-system (which the VM's need exclusive access to, to boot up as fast as possible).

 

What kind of real-life work could I do to create so much CPU usage?

 

I know the title of the thread is real-world tests, but could you bend the rules a tad and run w/ Prime95 or Hyper-Pi?

 

Maybe video encoding/filtering.

 

Does folding at home count?

 

Select some highly parallelized program and run it. You really haven't done anything that makes use of hyperthreading, let alone a four core processor.

 

A few finite element simulation software comes to mind as a CPU driven scenario. Running 3d CFD on comsol 4.0 stresses my CPU almost as much as prime95 for example. It's also a RAM hog

As namaiki said, video encoding too, you could use handbrake for example and re-encode a video you already have.

 

second on handbrake.

 

Just look up some reviews that benchmark the processors and look for yourself at what hyperthreading helps with. The work has already been done for you.

 

Hyperthreading a dual-core probably has some benefit because there are things out there that will make use of 3 or 4 virtual cores, but hyperthreading on a quad seems largely pointless for most workloads.