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[Max] Bug Reporting / Re: Very slow geometry phase 10x slower than old pc
« Last post by webuilddreams on Today at 13:24:26 »I hope solution for your problem is found, but I will like to stress that if in some case you have non-retail stepping (ES/QS/etc..), the issue can be with on-chip memory controller which creates certain spiral of firmware/OS issues that can manifest under certain workloads (whether it's scheduler issues, CPU groups, NUMA nodes, etc..).
So if Corona team received fully retail unit (which in 2024 means all-in-one system for most Epyc stuff), they might not be able to replicate your issue.
It's bit risky proposition to build custom multi-CPU servers today, too many variables with zero support. Super hard to investigate and find what can be culprit.
Not saying that's the case, just be prepared.
Nice to know that Corona devs got the machine though.
Hi we have a single retail Epyc 9754 (so no Numa nodes), we ruled out that the processor (and the whole system) is the culprit:
the slow geometry phase is caused by a particular step 'Embree scene calculation'.
The epyc is in the calculation of the 'Embree scene building' step very slow, 10x slower than for example a ryzen 5900x (12 cores)!
So to rule out that the Epyc cpu is slower when it comes to Embree calculation we want to test this slow Embree scene calculation and we tested it with Embree benchmarked software : phoronix-test-suite benchmark embree, the result was :
AMD Epyc 9754 : 127 frames/sec
Compared to
AMD Ryzen Threadripper Pro 7995WX : 116 frames/sec
Conclusion the Epyc is a bit faster in Embree calculations compared to a 7995WX (96 cores) so our system is not the issue, could it be the Embree version inside corona ?( Corona using old embree version?)Intel Embree is currently at version 4.3 do you know what version currently is used in Corona 11.1?