Hyper-threading technology

Hi
Does anyone know how Solidworks react on Intels Hyper-threading
technology. Will SolidWorks see it as one or two processors?

Kind regards

Klaus Sabroe

 

I posted this here some time ago (thread was "more RAM or Dual Processor")

Code written for multiple processors automatically takes advantage of
hyper-threading.
Further optimizations are possible, but will mostly be done by compilers, or
by using optimized libraries (see
http://www.intel.com/cd/ids/developer/asmo-na/eng/technologies/threading/index.htm)

However, you should realize that hyper-threading basically optimises the use
of the cpu by speeding-up thread switching, but you still have 1 processor
to do the math. So you can expect your system to be more responsive when
loaded, but hyper-threading probably won't speed-up your SW rebuilds...

 

We tested with PhotoWorks. Disabling the hyper-threading improved rendering
time dramatically - 40 minutes, down from 60 minutes, on our test assembly.

 

HT with 1 cpu is actually slower using SW. I do not see where it helps
with PW2 either.

The nice thing about HT is with multiple apps running smoother but not
really faster. (example running audio, video apps and SW at the same
time, no noticeable interruptions in audio/video... turn HT off, you
will see and hear interruptions.)

So, if you have (2+) SolidWorks open, yes, HT does help but that's
relative to what you are doing but it does not speed up SW.

The real advantage of HT is when you have 2 or more cpu's (= ~4 cpu's).

Anyhow, it's a easy test. Reboot, turn HT off in your bios and test the
difference.

...

 

Hi

Thank you for your response. I did not think that HT would give me any
performance improvements but I am not sure wheather the Windows will
se it as one or two processors as it is one physically, so I wanted to
ask. Actually I am having trouble finding the best Intel processor
without Hyper-Threading. I have been looking at Intels homepage and I
do not think it is clear.

Kind regards and have a nice weekend

Klaus

 

Klaus,

With HT on, windows does see it as virtually 2 cpu's.
Not sure what non-HT cpu's are remaining they exist and the vendor will
know enough which does not have HT?

Otherwise, nothing really wrong with HT and you can turn it off.

...

 

Hi,

I tried solidworks with hyper-threading and solidworks doesn't work well. If
you need power it's not the good way. In fact it's slower with
hyper-threading... In the task manager I can see two windows during a
solidwork session (like two processors). Each pseudo-processor have 50% of
the job....but if I want to open a big file or if I want to make a sldwg,
solidwork shutdown quickly without warnig and you lost everything.

Yours truly

Yves Rossignol ing. (engineer)

 

nothing surprising here. see below

you should report this to SW support.

You definitely have to understand what hyperthreading is, and how different
it is from dual procs.
see http://en.wikipedia.org/wiki/Hyper-threading and especially note:
"Hyper-Threading works by duplicating certain sections of the processor
-those that store the architectural state
-but not duplicating the main execution resources."

So, once more: (I posted this here some time ago )