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byte_fx
05-29-2006, 05:10 AM
Ordering a Power Mac G5 soon.

How does the G5 Power Mac organize it's memory re Lightwave?

Can each cpu access 4 gb or is the memory pooled so that only 4 gb of ram is needed for LW itself - not including ram needed by the OS?

Thanks

byte_fx

Captain Obvious
05-29-2006, 11:49 AM
The memory is not CPU-specific, and all of the processor cores can read from the same memory.

byte_fx
05-29-2006, 06:57 PM
Cool.

Thanks.

Saves a bundle on ram for Lightwave.

byte_fx

Hector Pascalid
06-01-2006, 12:17 PM
Cool.

Thanks.

Saves a bundle on ram for Lightwave.

byte_fx

If you can get a QUAD get one. I am running one with 2.5 gb only. Lightwave seems not to care much about the ram but you can set it to use the full power of the processors. I have the multithreading set up to 8 and the increase in render speed and cpu power usage is significant.

byte_fx
06-02-2006, 11:12 AM
Probably going with dual core 2.0 for now.

It'll give me a chance to check out OS X and some Apple software.

If all goes well in that regard then the Apple Intel version of a Quad is next buy.

Hope to phase out my Xeon/Windows systems over the next couple of years.

byte_fx

Hector Pascalid
06-02-2006, 12:43 PM
Probably going with dual core 2.0 for now.

It'll give me a chance to check out OS X and some Apple software.

If all goes well in that regard then the Apple Intel version of a Quad is next buy.

Hope to phase out my Xeon/Windows systems over the next couple of years.

byte_fx

I am not sure if lightwave will run as fast on an Intel Mac as on a PowerMacQuad because it hasn't been released as an Universal Binary yet.

byte_fx
06-02-2006, 10:11 PM
Neither has a top of the line Intel PowerMac.

At present it looks like it might use the 64 bit Quad Core (or Core Quad if Intel follows the Core Duo naming theme) that Intel plans to release in Q1 '07.

At least that's the most likely scenario at present.

Supposedly the next Core Duo model release and all that follow will be 64 bit.

But I've learned to wait and see.

I'n the meantime I can run the Mac version of LW on the PPC PowerMac and play around with Final Cut and other Apple Universal Binary apps to see how well I like them.

They won't run as fast as on a Quad but neither will I have a lot of $$$$ tied up in a piece of hardware.

If I like OS X ad beyond and the Apple apps then they can be switched to an Intel version of the Quad.

And LW should - I hope - be Universal Binary by 9.5 at the latest. So it can be moved to a newer Mac as well.


byte_fx

toby
06-03-2006, 03:03 PM
Quad-cores already? Sweet.

It's just a guess, but aren't software developers behind in getting their apps to be fully multi-threaded? It seems like a dual quad-core machine would have half it's cores idle even during heavy loads. As it is, my 2 year-old dual G5 can render with 2 copies of LW more efficiently than 1, I actually get 2 frames rendered in less than twice the time it takes to render 1, at 8 threads.

LW9 may change that actually, it seems to split up the frame dynamically :D when one thread is finished another thread will split in two!

Yes I've had too much :caffeine:.

Captain Obvious
06-03-2006, 04:57 PM
Some renderers have better multi-threading than others. Typically, bucket renderers (like Photorealistic Renderman, mental ray or modo) thread much better than the ones that just divide the image into one segment per thread, like Lightwave does. There is no real limit to the number of render threads possible, and I don't see why four (or even eight) would be a limit at all. There are plenty of people running dual dual-core machines today, and I've heard people report >100% speedups in Fprime on the quad G5 (more cores, more cache and faster RAM).



LW9 may change that actually, it seems to split up the frame dynamically when one thread is finished another thread will split in two!
LW9 does that? Cool! While I still prefer bucket rendering, that's a big improvement! :)

toby
06-03-2006, 05:09 PM
Yes, I was wondering about bucket rendering - I've only used one renderer that does it, VRay, and it seems that you'd still have to have the option of rendering many buckets at once - I only saw the option of one or two buckets.



LW9 does that? Cool! While I still prefer bucket rendering, that's a big improvement! :)
Yea it's probably part of the improved speeds, it's many, many times faster, probably the biggest speed improvement any package has ever seen. You also get your Limited Region renders split up evenly, fully multi-threaded.