TG 2 Preview 3 (alpha) Render Times Mac Pro Dual proc quad core

Started by DeanMann, April 29, 2008, 12:46:56 pm

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DeanMann

Hi
I am running a Dual Xeon 3 Ghz Proc Quad core Mac Pro with 8GB Ram and Nvidia Quadro FX 4500 graphics option
Preview 2 scene 37:08 mins 3467165 Micro-triangles 800 x 600

Preview 3 all eight cores detected Min 1 max 16 threads set

Over 1hr 07 mins 13 sec 0 micro-triangles reported - same scene - But Image looks improved?? Sky renders better and surface detail is less grainy.

Will some scenes take longer to render? But no improvement using 8 cores.
Mac OSX 10.5.2 (Leopard)

If you need more info on the set-up let me know

Dean

Matt

Some scenes may take a little longer to render in the new version if it only uses 1 thread. But I would expect most scenes to render much more quickly if it is able to use more threads as it appears to on your machine.

I'd be interested to know how long it takes to render the same scene with different numbers for max threads. Tests with 0, 1 and 2 would be useful.

Matt
Just because milk is white doesn't mean that clouds are made of milk.

red_planet

I'm experiencing similar problems with a dual 3Ghz Xeon Mac Pro  OS X 10.5.2. 2Gb RAM

Render default scene (i.e no terrain) with 8 threads(cores) time 8 mins (TGTP 1.9.88.1)

Render default scene Time 1 min 34 secs (TGTP 1.9.04.1)

Report submitted to Planetside support but may have been caught in spam filter...??

Rgds

Chris

Matt

Chris, what about with max threads set to 0, 1 and 2? (Leave min threads at 1.)

Matt
Just because milk is white doesn't mean that clouds are made of milk.

red_planet

Matt.

Will try  8 core @ work tomorrow, just ran similar test on old PPC dual core G5 ( Dual 2Ghz, Mac OS X 10.5.2) @ home similar results but not quite such a drastic differential.

TGTP 1.9.88.1 7 min 02 secs thread min set to 0
TGTP 1.9.88.1 7 min 04 secs thread min set to 1
TGTP 1.9.88.1 6 min 57 secs thread min set to 2

TGTP 1.9.04.1 5 min 55 secs

On Vista PC - Home Premium (Dell XPS 210, Intel Core 2 6300 1.8 Ghz, 4 Gb RAM ) Time to render 2 mins 27 secs ! (TGTP 1.9.88.1, 2 threads) 4 mins 27 secs (TGTP 1.9.88.1 1 thread)

As a side issue, even though I have purchased Deep+Animation, the version running under Vista still won't let me access the animation features.  :'( (No great panic on that one, just a heads up)

Rgds

Chris

Doh .. you said max threads... too late tonight.. will repeat tomorrow !! ::)

Matt

I knew I shouldn't have added that min threads parameter... I had wanted to just have a max thread parameter to avoid these kinds of mixups ... :)
Just because milk is white doesn't mean that clouds are made of milk.

Matt

Quote from: red_planet on April 29, 2008, 07:34:26 pm
As a side issue, even though I have purchased Deep+Animation, the version running under Vista still won't let me access the animation features.  :'( (No great panic on that one, just a heads up)


That's strange. Did you buy Deep first then later buy the Animation upgrade? The only thing I can think of is that you have two keys and it's using a different key to the one you think it's using.

Matt
Just because milk is white doesn't mean that clouds are made of milk.

jo

Hi,

I've been doing some default scene renders on my dual G5 and Intel iMac. With two threads it is faster, but not dramatically so. With earlier development builds I saw more improvement, but they also weren't doing everything they should. I'm going to do some profiling to try and see what's happening.

One thing I have seen recently on an Apple developer performance mailing list is that there are some cases where the Mac OS is slower than Windows and Linux when it comes to certain multithreaded programming constructs. It's been a bit of a problem for a few people lately. These problems seem to be worse the more threads you're using, so this may be a case where an 8 core Mac runs into a bit of a dead end. However I just thought I would mention it, and I haven't yet been able to establish if these sorts of things are a problem for TG2 Mac. Unfortunately I don't have an 8 core Mac to test with :-).

Regards,

Jo



DeanMann

Hi Jo

I run Cinema4d using 8 cores on the Mac Pro and it is really fast and the machine is faster than my Armari x64 Windows machine also with dual 3 Ghz Quad cores and the same memory so I do not quite agree about the speed. I do know that some developers are finding optimisation difficult though.

I will try some tests later today with different threads - you say reduce the max threads?

Let me know any other tests you want me to try - I have not tried the terragen on the Windows 8 core - do you want me to try this?

Dean

Matt

A warning if you are using 8 threads. This alpha build isn't very well behaved with a large number of threads because it uses up to 150Mb per thread for the ray tracer (although it shouldn't be a problem with low resolution renders). 8 threads will therefore put an extra strain of 1 Gb above what would be required for 1 thread. The increased memory use may lead to extra virtual memory swapping and reduce performance (and increase the chance of running into memory allocation errors). I'm working on a way to share this memory between threads.

Matt
Just because milk is white doesn't mean that clouds are made of milk.

rcallicotte

Maybe my usage of 4 to 6 in the Minimum Threads entry textbox is why I have been running into errors.  Not sure.  I did have a render come up blocky with the "render skip" error that was only using 1 Minimum Thread.  If it helps, I could post the TGD here tonight (GMT -6).

So this is Disney World.  Can we live here?

Oshyan

Calico, do you have a system with 8 cores available? If not you're just needlessly increasing overhead. Currently even 4 cores eats quite a bit of RAM unfortunately. We're looking into enabling the switches on the development side that will make the /3GB switch work, as well as possibly allowing render tile threads to share data, but for now I'd recommend no more than 2 cores except for more simple scenes. There is also a memory leak that may be exacerbating the memory problems.

- Oshyan

rcallicotte

@Oshyan, I have the Intel Core2 processor Q6600 (2.40Ghz 1066FSB) w/Quad Core Technology and 8MB cache.  The memory is 4G of DDR2 SDRAM at 800MHz, which is setup with the /3GB switch.
So this is Disney World.  Can we live here?

Oshyan

With a quad core system you would never want to increase min threads over 4. There's just no good reason to. Currently you might even want to limit it to 2 for memory conservation. We're working on optimizing memory use and better utilization of quad core and higher systems should be possible in more memory-constrained situations in the future.

- Oshyan

red_planet

Small addition...

I withheld further testing on the 8 core Mac Pro until such time as I had the opportunity to upgrade the RAM.

Now running with 6Gb.. no difference. Still 8 mins+ for a bare render with 8 threads.  :(   (The initial GI pass seems to be very quick ...it's the rendering that's seems to be taking all the time.)

but !!!
Bare render max 1 thread ....... 5 Min 20 secs
Bare render max 2 threads ..... 1 Min 52 secs !!!!
Bare render max 3 threads ..... 4 Min 10 secs
Bare render max 4 threads ..... 6 Min 35 secs
???

I'm sure you'll figure it out.. the guys at Blender did, although I'm reasonably sure that the underlying cause is most likely very different, it may be worth noting that it was when rendering with the internal renderer in Blender that the problem surfaced.

Rgds
Chris