SU multi-processor usage

remus · 11 Apr 2008, 22:35

Just a note that might be of mild interest to a few people, it appears that although SU cant take full advantage of multi core systems, it still runs on both cores at the same time.

As an example, see the screenshot below:

During this time, i only had SU running, and it said it was running at 50% processing power in the process' list.

Weird stuff.

lewiswadsworth · 11 Apr 2008, 23:42

On my computer, running in XP SP2 on a Core Duo Extreme, I only see changes in one of the four processors when I do anything with SketchUp. Rhino, my other workhorse program, supports multiple processors, and I see changes in every processor's graph when I perform major operations.

juju · 12 Apr 2008, 10:28

remus, that could also be because of services (anti-virus, etc.) running in the background. The OS will distribute computing load.

remus · 12 Apr 2008, 10:42

I see what your saying juju, but if SU is running at full capacity (50% of the processing power) you would surely expect it to just max out one processor, rather than being spread across both processors.

solo · 12 Apr 2008, 13:22

There could be another reason, have you checked the priority level of SU within the taskmaster menu? and which core it's allocated to?

remus · 12 Apr 2008, 14:01

priority is normal, core affinity is set to both cores.

tim · 14 Apr 2008, 04:35

Basically there is no chance that SU would be the only thing running - OSs just don't have only a single process/thread wanting cpu time these days. It's entirely possible that your copy of SU is running for a moment on one cpu and then getting some time on the other. It will depend on the scheduling policy used in the OS, the other threads, interrupts, events... etc.
If SU is running and something 'more important' demands time then SU will get put on the back-burner for a while. If some time becomes available on the other CPU you might well get it. The downside of swapping cores is that the content of the cache(s) that you were benefiting from is lost. Well, unless there is some very clever stuff going on that I've not heard of.

remus · 14 Apr 2008, 08:31

I'm in agreement that it certainly isnt runing on multiple processors, i just thought it was a bit of a curiosity