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Menaries
08-03-2006, 09:12 PM
I know this may seem like a silly question. But with Max and Maya just coming out with 64-bit versions of their programs, what does that mean exactly? I guess my question is, why does it matter that Max and Maya now have 64 bit versions, and how will that benefit 3D artists?

Thanks!

lots
08-04-2006, 12:01 AM
Depends on what Autodesk has added. Most 3D apps that have made the switch (XSI, LW, C4D) generally all now support absolutly huge numbers of polygons in a scene. In some cases (C4D) there has been noticable performance gain, due to a leaner binary (no need for legacy support). In general, for 3D, the biggest gain is the ability to use up to 128GB of RAM, and 16TB in virtual space (though thats probably not very useful :P). This means more objects, more textures, more of everything basically. You can spend fewer passes rendering a scene full of a very large number of objects, that would otherwise occupy all the available memory in a 32bit system (4GB at the most).

Things like XSI's Gigapoly, or the lightwave demonstration at WinHEC 2005, where they opened 20 or so copies of the full Battle Star Galactica, where 32bit LW could barely handle 1 show just how much more can be done at once on the 64bit versions of these apps

The problem area here, is plugin support. I believe in all the 3D apps that have a 64bit port, you need a 64bit version of your plugins in order to do anything with said plugins (scripts should work ok, but binary based plugins wont). 32bit plugins will not work on a 64bit 3D app. That may cause an initially slow uptake of the 64bit versions of Maya and Max, but once more developers hop on the 64bit bandwagon, more plugs should arrive.

705
08-04-2006, 01:52 PM
whattabout d performance? Do 64bit CPU gives major advantage to rendering time?

Srek
08-04-2006, 02:16 PM
whattabout d performance? Do 64bit CPU gives major advantage to rendering time?
In short: No

Long answer:
There are some additions that come with the 64 Bit extension (mainly new registers) that can lead to an increase in performance, but nothing that is realy noteworthy.
The speed advantage in CINEMA 4D 64 bit is mainly due to old CPUs not supported anymore, like lots already pointed out.

Cheers
Björn

Elekko
08-04-2006, 02:37 PM
What I remember, a demonstration video at some expo... they showed Maya 64-bit running. And what I saw was that the guy was playing fluid effects animations in real-time and at the same time working with other stuff in Maya user-interface...

Elekko
08-04-2006, 02:38 PM
And that was something that would be laggy on my 32 maya and pc...

lots
08-04-2006, 10:12 PM
Excatly. But that is because of the limited memory space in 32bit applications. 64bit allows for huge data sets to be open all at once, thus in effect, it appears faster.

Basically from my POV (lightwave) you can render millions of polys, have very complex models lights and textures, lots of other effects, and still finish a render. The big area that 64bit would be much faster is in RAM consumption. If your scene is say, 8 GB in size during render, and around 4 or 5 during UI interaction, a 32bit app would tend to crash, or become VERY slow (due to paging to disk tricks). So slow it would basically be unusable in any way. A 64bit app would have full access to 8GB and more (assuming your computer has that much RAM). Thus it is no longer bottlnecked by the speed of the hard drive (which is orders of magnitude slower than RAM), since every bit of data fits into RAM.

Now the Maya devs may have improved performance of 64bit Maya by doing what I mentioned above (removing support for older hardware). This makes the binaries more lean, and more specifically optimized for the absolute latest CPUs. In C4D, this gave a good boost to performance over regular 32bit. Similarly Maya may prove faster in 64bit if properly designed.

tecton3d
08-04-2006, 10:30 PM
In general, for 3D, the biggest gain is the ability to use up to 128GB of RAM,...

@lots, are the software developers (for maya, max, lwave, cin4d, etc) still a bit behind regarding this 128gb limit? I mean, I can't go splurge on a system based off an IWILL DK88 (http://www.iwill.net/product_2.asp?p_id=102&sp=Y) which is 64gb RAM capable and expect Max64/Maya64, on an XP64 system, to access all 64gb of ram?!

I'd like to think this would happen, as it would vastly change the way some of us work, but am somewhat doubtful as the seemingly low, 2.5gb (or whatever it is) limit of 32 bit max is not even close to the capacity of this new 128gb RAM accessing, 64bit system... kindof overwhelming in when you look at where we're coming from.

basically, can the software at this point, take FULL advantage of 64 bit if the limit is indeed 128gb of RAM?

I owe you/someone a guiness for asking such a question : )

lots
08-05-2006, 12:28 AM
@lots, are the software developers (for maya, max, lwave, cin4d, etc) still a bit behind regarding this 128gb limit? I mean, I can't go splurge on a system based off an IWILL DK88 (http://www.iwill.net/product_2.asp?p_id=102&sp=Y) which is 64gb RAM capable and expect Max64/Maya64, on an XP64 system, to access all 64gb of ram?!

I'd like to think this would happen, as it would vastly change the way some of us work, but am somewhat doubtful as the seemingly low, 2.5gb (or whatever it is) limit of 32 bit max is not even close to the capacity of this new 128gb RAM accessing, 64bit system... kindof overwhelming in when you look at where we're coming from.

basically, can the software at this point, take FULL advantage of 64 bit if the limit is indeed 128gb of RAM?

I owe you/someone a guiness for asking such a question : )

The low 2 to 3 GB limit of 32bit apps is actually a limitation of the hardware. In most cases, 32bit hardware has a 32bit address bus. This means that the most memory a 32bit address bus can see is 4GB (2^32 bytes). The reason that applications cant get more than 2 or 3GB, is because Windows and the PCI bus need to reserve space in memory in order to function properly, thus no 32bit app really has full access to 4GB. There are exceptions to this rule, Intel's Xeon has a 36 bit address bus (before the appearance of EMT64), which required Windows to do some fancy tricks to be able to address this extra space (PAE), which has a performance hit, and only some software support it. In addition to that, 32bit Windows, like the hardware, only had the ability to address 32bit address spaces (without any special tricks).

Windows 64bit supports up to 128GB of physical RAM. Therefore it should be available to the software. I suspect that all the software written to be 64bit, should be able to address almost all the space windows can (reserving some for OS and various buses), which in the grand scheme of things should not be too difficult to impliment in the code.

For example, I have seen people using 8GB of RAM with LW 64bit, and I have not heard of any limit to the amount of RAM that it supports (outside of what Windows limits). And to be honest only very rich people have the money to put down to actually BUY 128GB of RAM :) not to mention the expencive motherboard and CPUs...

Srek
08-05-2006, 11:01 AM
The 128 GB barrier comes as a licensing restriction of Windows XP 64. The 64 Bit apps can make use of the full Tera Byte if the OS allows. If you use Windows Server 2003 you can use more then 128 GB physical RAM, the exact amount depends on the version you get..
Cheers
Björn

tecton3d
08-07-2006, 04:19 AM
... as usual ~ thanks for clearing things up lots and srek:beer:

and I thought I was special because my K8WE can handle 16gb of RAM:shrug:, anyway - where are all the 128gb capable mobos? If the working file size increases proportionately to this huge system memory jump (perhaps they won't but hypothetically...) allowed by 64bit, isn't graphics hardware and storage performance lagging a bit behind? For me, a huge file is 250megs or so and that's with my lowly 32bit system and 4gb of installed ram, then a file of 1gb could easily be the handled by a system with 16gb of ram ~ right? Well, the normal laws of viewport and graphics card limitations still apply but if files are organized in a somewhat logical manner, working with files, of what would seem like unheard of sizes now, can become the norm.

why am I both extremely confused and exited by the potential of 64 bit?!

lollygag
08-07-2006, 06:24 AM
Bout 8 dollars.

tecton3d
08-07-2006, 11:50 AM
Bout 8 dollars.
LMAO!:bounce:

lots
08-07-2006, 12:56 PM
Opteron boards, generally have alot of Memory capacity. Unfortunately due to some of the limitations of DDR, the RAM density is not very good, thus the only currently available Opteron boards with support for 128GB RAM are the 8 way boards, which have 32 memory slots, 4 per CPU socket. The K8QW, and similar boards support this. There are boards from other makers, but generally its all about the same story.

I suspect once the Socket F based Opteron boards come out, supporting DDR2 among other things, the density should increase, and the number of sockets per controller (CPU in Opteron's case) will go up.

Similarly the Woodcrest based Xeons have motherboards that come with up to 16 memory slots, each with the ability to support some pretty dense modules, if I remember right.

Basically all these boards are some serious $$ :P

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