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[Max] Resolved Bugs / Re: Better CPU multithreading support?

« on: 2013-06-20, 15:49:00 »

That's great, thanks.
Vray actually had a similar problem initially, the light cache was acting weird with the E5 xeons. They got it fixed pretty fast.

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[Max] Resolved Bugs / Re: Better CPU multithreading support?

« on: 2013-06-20, 03:50:10 »

gi.secondarySolver set to 1 helped:
E5 - 18.2M
x5680 - 16M
So I guess HD is what slows down the E5?

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[Max] Resolved Bugs / Re: Better CPU multithreading support?

« on: 2013-06-19, 20:49:53 »

Quote from: Keymaster on 2013-06-19, 17:11:15

The problem is not with sequential bandwidth, but random access, which is sadly completely different story

But random access can't be lower then the previous generation xeons, right?
What I see is 54GHz (combined) new generation cpu is 15% slower then the previous generations 48GHz...

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[Max] Resolved Bugs / Re: Better CPU multithreading support?

« on: 2013-06-19, 16:59:11 »

Quote from: Keymaster on 2013-06-19, 00:12:33

Because the raw CPU computation in corona is optimized pretty well, you will hit the memory bandwidth limit pretty hard with huge number of threads. But it might be possible you are hitting other limits:
Frame buffer access: try editing the export.conf file of the benchmark, change int pathtracingSamples = 16 to 128, what will the comparison look like?

I tried that, speed dropped by about 20% on both computers.
I'm not sure if memory bandwidth is a problem, according to intel it E5 has almost 2x more bandwidth than the x56xx platform.

http://www.intel.com/content/www/us/en/benchmarks/server/xeon-e5-hpc/xeon-e5-hpc-memory-bandwidth-stream.html

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[Max] Resolved Bugs / Re: Better CPU multithreading support?

« on: 2013-06-19, 16:54:35 »

Quote from: Juraj_Talcik on 2013-06-18, 23:48:00

Judging by 3930k unclocked score of roughly 5mil rays, the dual top E5 should easily scale to atleast 10.

Well, in my Vray tests dual e5 is about 100-120% faster then two mildly overclocked 3930k machines (distributed render). That's why I got dual cpu systems - I don't want to have 5-6 computers sitting under the desk in my home office.
Corona is a different story though.

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[Max] Resolved Bugs / Better CPU multithreading support?

« on: 2013-06-18, 16:46:01 »

Seems like Corona is not optimized that well for the large number of cpu cores.
I'm using these 2 machines:
dual x5680 @ 4ghz (12 cores - 24 threads)
dual e5-2689 @3.4ghz (16 cores - 32 threads)
Corona benchmark results are 8.2M rays/s vs 7.5M rays/s in favor of x5680 system.
But both Vray and C4D results are exactly opposite - e5-2689 is significantly faster, by about 15% (which makes sense considering never generation and number of cores difference).
Is this something you could resolve in future releases?
Thanks.

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