Dual AMD EPYC Cpu not preforming in VRay

[vlado]

I'm in the process of organizing an EPYC system for profiling, but it takes a while to sort it out.

Best regards,
Vlado

[tsmithf2]

That's good news, as there's clearly significant potential there to be unlocked, looking forward to the update

[tsmithf2]

To update our investigation we have just updated the bios for the H11DSi-NT motherboard to the latest 1.3 (H11DSI9.625) version and we have seen a 50% performance increase in Vray

[I-REEL]

We have the same experience here. New render nodes with Dual Epyc 7281 have rendering performances close to our previous / regular nodes (Dual 2630 V4).
We tried the CorePrio util (supposed to improve windows scheduler / NUMA performances for single CPU system) with no noticeable improvement.
I'll try updating Bios to see if there is improvement and I'll report here if there is improvement.

[vlado]

We just ordered a dual EPYC machine couple of days ago, it will take a bit of time to get it in the office, but then we will be able to do some profiling.

Best regards,
Vlado

[vlado]

So a small update: the machine is in our office already; we will be doing some tests/profiling next week.

Best regards,
Vlado

[tsmithf2]

Hi Vlado

Do you have any updates?
Have you experienced the similar lower performance in vray with your EPYC system?

Even after a bios update, our machine is still performing far slower than expected.

Kind Regards

[I-REEL]

With all the hype going around Epyc, guess we should have an update soon
Best regards,

Rapha

[Vipera]

There is a serious problem with render time on AMD CPU. I have found one parameter which affects the render time significantly on AMD to compare with Intel CPU. Please check my post here.
https://forums.chaosgroup.com/forum/...34#post1060034

[vlado]

The new Threadripper 3xxxx CPUs are much better for rendering than Epyc CPUs.

Best regards,
Vlado

[Alex_M]

Is this due to the lower average all-core frequency compared to the same core count Threadrippers or is it something else?

[I-REEL]

Alex_M I guess it as to do with Numa and threads handling. You can find some investigation on this subject at bitsum coreprio page.
vlado : If I read you fine, we shouldn't expect an update in Vray anytime soon that would improve Epyc rendering results, right ?

[vlado]

I'm afraid there is nothing we can do about the performance of Epyc CPUs through software updates.

Best regards,
Vlado

[seandunderdale]

Some of the highest scores on the vray benchmark are Epyc setups...whats going on there?

[sirio76]

Benchmarks don’t necessarily represents real world since difference between workloads may vary a lot.