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sykosys
10-21-2005, 02:51 AM
I've got a problem. I just built a new machine:

Dual Opteron 270
Tyan K8WE
4GB OCZ Ram (per Tyan's spec)
2X Quadro FX3400 PCIe-x in SLI
2X Seagate Barracuda 250GB mirror raid
1X Seagate Barracuda 250GB non-raid.
Windows XP X64

My old workstation is:
Dual Athlon 2800+
Tyan MPX
2GB Kingston Ram (per Tyan's spec)
Quadro FX3000 AGP
Multiple IDE HDs
Windows XP

So the new is 8GHz of Opteron 64 bit glory, and the old is 4GHz of ancient athlon. (Yes I know that max won't appreciate any speed by 64b, and possibly a slight relative slowdown in that environment.)

So, I go to render in Max 7. Scanline & finalRender. Rendered 4 different scenes, ranging from 1 minute - 13:50 on my old workstation. Several of them are scenes that are 99% multithreaded tasks.

I render on my new workstation, all excited. But I only get a 50% increase in speed. What? That can't be right? Being that the opterons is a class above, and all the hardware (ram, et al) is so much faster, I'd expect more than 50% more speed, especially considering how much the thing cost!

It's the same story in Max 8. I've posted this issue on the max board, and it was suggested that there was some issue with affinity not attaching... but I've tested that not to be the case. All the drivers are up to date, nothing in the harware manager would suggest otherwise.

By this line of logic, two opteron 244s in this machine would be exatly the same speed as my 3 1/2 year old workstation. That can't be right...

... can it?

SatoriGFX
10-21-2005, 03:40 AM
PowerNow may be the cause becasue it can throttle back cpu speed when it shouldn't really be doing so. You should be able to disable it in your bios (or some say you can just set your power management to Always On or Home/Office Desktop).

Adam.

sykosys
10-21-2005, 01:36 PM
PowerNow may be the cause becasue it can throttle back cpu speed when it shouldn't really be doing so.

Nope, tried that and found 0 effect. :( Any other ideas?

SatoriGFX
10-21-2005, 01:46 PM
And you don't have any of the AMD drivers installed (Cool and quiet, Power Now)?

I have no idea what else might cause this. You are using XP64 so you don't need Microsoft's dual core hotfix. And since you don't use any power management/cpu throttling stuff the /usepmtimer boot.ini switch should have no affect either.

Sorry, no idea. Good luck.

Adam.

Cronholio
10-21-2005, 03:04 PM
By this line of logic, two opteron 244s in this machine would be exatly the same speed as my 3 1/2 year old workstation. That can't be right...

... can it?

It is possible (and probable) that whatever it is you are rendering to test your hardware is completely bound by the power of your CPU, fits entirely into your memory footprint, and further is not complex enough to take complete advantage of all the hardware, in which case yes, you probably wouldn't notice much difference between an Opteron 244 and a 2800. If by 50% faster you are saying that your current setup is rendering these test scenes in half the time of your old machine then, everything is probably working fine. Waht you need to do test with something more complicated, a large scene that has lots of caches, multiple frames, using a renderer that is distributed and supports things like procedurals and deferred asset loading.

lots
10-21-2005, 05:14 PM
I'm not a Max user, but I would assume you can also set the thread number of the renderer. Try setting it to more threads, since you have 4 physical CPUs, try setting the thread count to 8.

enygma
10-21-2005, 05:39 PM
http://www.xbitlabs.com/articles/cpu/display/opteron-ws_16.html

I think this benchmark might put some things into a bit of perspective on the dual core Opteron front. Keep note that the Athlon64 X2 4800+ is very similar in performance to dual Opteron 250s. 3ds Max rendering only shows a 47% improvement over the 4800+, meanwhile, in the Zoo Render benchmarks for Maya, there is a 93% improvement.

I think there may be a slight software issue in 3ds Max when it comes to utilizing 4 cores in one system. If you were to render in Maya, you may see exceptionally better results.

lots
10-21-2005, 08:07 PM
If you're using mental ray, I believe that the license on Max only covers up to 2 CPUs. The other two will not be used. You could check by opening up task manager and watching CPU utilization and see if all CPU graphs max out...

daraeill
10-22-2005, 03:39 AM
another consideration is windows itself...the 64-bit edition is still very new as is the recompiling move that alot of the software manufacturers are heading towards...as with any change of this magnitude all the bugs/inefficiencies/etc have not come even close to being ironed out...i'm sure that in the future once 64-bit software compiling has fully gone mainstream that you'll notice a bit more improvement, but probably not that much more.

also...just because 64 is twice 32 or you have double the number of processors, that doesnt translate into EVERYTHING running at literally twice the speed...

sykosys
10-22-2005, 04:07 PM
I should re-iterate; I wasn't expecting a 900% speed increase. I was just expecting to have more of a speed increase than if I went out and bought myself a pair of dual 2800+ render boxes.

However, based on the link posted by enygma, it could well be that max is just being a pig.

Sadly, though, the conclusion has to be that I completely wasted my money. I would have been much better off to overhaul my current workstation with some extra ram and SATA HDs/SATA card. And then bought six like render boxes. :(

I'll just try to take solace in the fact that as software starts to come out in 64b that I'll be able to take advantage of it. Like those poor saps who upgraded to Windows 32b from 16b.

Oh, and lots - I think Max 8 has unlimited MR nodes. Not that I've ever used it, but its there.

Rabid pitbull
10-22-2005, 04:26 PM
Oh, and lots - I think Max 8 has unlimited MR nodes. Not that I've ever used it, but its there.

Are you serious?? I would be shocked s***less if that was true.

As for the software not taking full advantage of the system, sucks but I bet it will be resloved soon enough.

sykosys
10-22-2005, 06:35 PM
Are you serious?? I would be shocked s***less if that was true.

As for the software not taking full advantage of the system, sucks but I bet it will be resloved soon enough.

Direct form the Autodesk press release (http://usa.autodesk.com/adsk/servlet/item?siteID=123112&id=5776450&linkID=1977925)...

"Autodesk introduces the industry’s first scalable, unlimited mental ray network rendering option specifically for 3ds Max. "

I'm not so sure about it being resolved soon, frankly. Autodesk isn't exactly lightning on its feet, and with 8 having been released, I wouldn't expect any updates for at least 2 months. I might as well wait until then to get new 270s; keeping in mind that I already have a pair of 244s sitting here unused.

MCronin
10-22-2005, 07:31 PM
Unlimited render nodes is not the same thing as a ditributed renderer. I'm not sure what Autodesk's implementation is (everyone does it differently) but usually unlimited render nodes means you can render on as many computers as you wish (One full frame per processor) but when it comes to distributed rendering, only one possibly two processors can be used per frame. You really should check your process manager and see how many processors are acutualy being used by Mental Ray. If you want to use all four processors, you are probably going to have to get Mental Ray standalone licenses for 4 processors.

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