Big poly~ @parallel performance problems in Windows 10 vs Mac
I have a Macbook Air running Sierra with a 1.7 GHz i5 and a 12 core Dual Xeon Windows 10 workstation at 2.8 GHz.
I'm running the same version of Max (64-bit) and the same patch. It is a pretty simple test patch that parallelizes some oscillators in a poly, creating 64 poly voices/instances, each one containing a cycle~ or phasor~ object.
Setting my poly~ to @parallel 1 on the Mac reduces my CPU usage to 12 - 15% from 20 - 25% at @parallel 0. Almost half the utilization and everything works as I'd expect.
Setting poly~ to @parallel 1 on the Windows takes my CPU usage from 5 - 10% all the way to 60% - 100%! Strangely enough, this effect on CPU utilization seems to rise with threadcount: if I send the message threadcount 2, the CPU utilization is at 20%, and the more threads I add the higher the CPU utilization.
Do I need to initialize some kind of driver or setting on the Windows version? Something in the bios maybe for the CPU?
Turning off Hyperthreading actually gave me a decent 5% - 8% boost on my current Max patch, but didn't fix my parallel issue.
Also, the CPU load in my task manager doesn't seem to correlate to the one in Max MSP..
When my Max CPU is at 100%, my task manager is at around 8% total.
When I set the core affinity in task manager and threadcount in Max it does actually seem to be producing the desired load on the cores. For example, if I set Max affinity to cores 0 through 3 and the threadcount to 4 (simulating a dual core) and look at the processor load in task manager at @parallel 1, there actually are loads on cpus 0 through 3 and no loads on cpus 4 through 23. In almost all cases the Max CPU goes up anyway though.
I can set the affinity and threadcount to other values simulating quad cores, hex cores, etc., but it's not just a matter of the Max CPU meter being wrong because once I hit 80-100%, I still get stuttering.
I'm suspecting it might be a driver issue on Windows with my interface. I'm going to try a few more variables with my setup then I may just install Mac on this machine, core audio is better..
I'd like to hear if anyone else has had success on Windows with more cores than the typical dual/quad or using a motherboard with two CPUs.
aubo, if you actually want others to say something, please share the patch. Thank you.
I will when I get a chance, I'm away from my computer.