RF Threading with new Intel i7 3930K CPU/ Win7x64

[FlorianK]

Hi,

it seems RF2012 (v070) has an issue with Hyperthreading on Intel's i7 3930-K architecture. The CPU's got 6 real cores, so with HT enabled I can see twelve cores in the Windows Task Manager's Performance Monitor. Realflow also finds twelve cores (Simulation Options -> Threads), but if I simulate (Standard Particles, haven't tried with Hybrido, yet) only every other core is used (due to Windows Task Manager).

At work, I've currently got a Dual 8 Core Xeon (not sure about the model right now), also with HT enabled. If I simulate the very same setup, all cores are used (incl. HT cores).

This might not be a bug or a big issue as Realflow performs well on my 3930K machine, but I found it worth mentioning (maybe Realflow could perform even better on this CPU...?)

EDIT: The same simulation (basically), Realflow hasn't been restarted, hours later...but this time all cores seem to be working on the sim. Strange.

[marnix@rckmn.nl]

mmh, that's interesting.

Have the same cpu chipset here and seems to be slow too.
Here it starts off quick when I just loaded RF and later on gets very slow.
Some sims are 10x slower than on a quad i7..

Did you ever had problems with it again?

[atena]

Thank you for the feedback, let us know if that ever happen again. It is strange indeed.

[marnix@rckmn.nl]

I've just send a benchmark to Gus about this issue.
In short...a 20 frame sim (1.000.000 particles) :

quad i7-2600 - 3.4Ghz, single HD, 8gb ram > 8m39
quad i7-940 - 3.0Ghz, RAID-0 HD, 12gb ram > 28m14s
hex i7-3930K - 4.2Ghz, RAID-0 SSD, 16gb ram > 39m55s

[mdonovan]

I have seen this behavior on our new DUAL XEON E5-2680 machines as well. Although not consistently ... I was actually curious if hyperthreading is slowing the machine down ... any thoughts ?

[FlorianK]

Hi Mike,

I made some tests a while ago (using RF2012) and in those tests HT was slightly faster than no HT. However, Realflow doesn't work pretty well on cerrtain CPUs (or at least parts of Realflow). At the studio I currently work for, we tested a sim using Realwave and Realwave ObjectSplash.

Simulating that scene was close to impossible, everything took ages at particle couns of less than 10K, simplified geometry and highly resoluted Realwave surfaces. The machine we used was an Intel Xeon X5690 (2CPU) with 24GB RAM.

We send the scene to NL support and Luis said he didn't have any troubles simulating it. However, the scene ran perfectly well on my Notebook (i72680K, 8GB RAM), we then tested the scene on a W5590 and there again it didn't run. So there it is definitely worth testing if the scene runs better on a different type of CPU.

[fip]

Realflow doesn't work pretty well on cerrtain CPUs

is there any other CPU configs that have been noted by others? this would be a useful nugget for those of us who are looking to upgrade their system thanks!

-fip

[marnix@rckmn.nl]

just played around with Realflow 2013 and there is still a significant slowdown on the i7 3930k

any chance someone figured out how to fix this?

[Oldcode]

I have an AMD Phenom II 3.2ghz with 6 cores. I'm thinking of upgrading to a AMD FX-9370 Vishera 4.4GHz with 8 cores. I usually get AMD because although not as good as Intel most of the time, I get much more for my money. The equivalent Intel chip would be hundreds of dollars more.

Right now I'm doing a shot with ~650,000 with 500 viscosity and needed substeps. It takes over 19 minutes per frame to simulate.

Although a good value, I have heard that Intel chips are much better for Real Flow than AMD, even at the same clock speed and number of cores.

Anybody else have information on that?

Thanks,

[gus]

just played around with Realflow 2013 and there is still a significant slowdown on the i7 3930k

any chance someone figured out how to fix this?

Hi Marnix,

How are you doing?
What drivers are you running on your graphics card?
I run the scene you sent me a while back yesterday and it behaved properly in our 3930k.
I wasn´t using the latest nVidia drivers. We found out that they have to fix them and hopefully there would be an updated driver soon that runs smoothly.

g-)