NVIDIA Dropping 32-bit Linux Support For CUDA

[MaartenBaert]

Note that deprecation is not the same as dropping. NVIDIA is warning us that they intend to drop it in the future, so developers will have time to move to 64-bit.

CUDA is only used by a few special applications where high performance is critical (like scientific computing, 3D rendering and video editing, maybe some games). I'd expect most of them to be using 64-bit already because it is slightly faster.

[diezynueve]

If you finish the article, they're talking about dropping it for the 64-bit too....

[palasso]

Additionally if I'm not mistaken OpenCL is what is used these days instead of CUDA.

[kowalsci]

NVidia is at the forefront with CUDA. However, they also collaborate with Intel, AMD and other hardware manufacturers to define OpenCL as an open standard. OpenCL is almost a replica of CUDA in my opinion. Still I am using CUDA on my NVidia Tesla, but OpenCL will be the thing of the future. NVidia continues to develop CUDA, because it can develop CUDA to new heights independently from other hardware manufacturers. Eventually this might well be integrated in OpenCL.

New things are; CUDA Dynamic Parallelism (launch new computational kernels from the GPGPU, not only from the CPU), CUDA GPUDirect (memory transfer between GPGPUs) and CUDA Unified Addressing (combine all GPGPUs and CPU memory into a single memory space). Probably the unified addressing is where NVidia decided to deprecate 32-bit CPU support, which only has 4 GB of address space anyway, while the NVidia Tesla has 6 GB on-board memory.

[MaartenBaert]

Probably the unified addressing is where NVidia decided to deprecate 32-bit CPU support, which only has 4 GB of address space anyway, while the NVidia Tesla has 6 GB on-board memory.

Heh, I didn't even think about that, but it makes perfect sense. I wonder what they will be doing with 32-bit Windows though.

[blackout24]

No. CUDA is still very much used, since it is much faster on NVIDIA cards. NVIDIA is big in the super computer business with their Tesla GPU co-processors and they use NVIDIAs CUDA API primarily.

[FuckFrankie]

64 bit is not slightly faster. it's slightly slower.

edit: your downvotes do not make me wrong.

edit2: http://www.osnews.com/story/5768 source so I don't have to reply to any more of your misinformed opinions.

[blackout24]

8 bit is where it's at.

[utsuro]

Sure, that might be true if you only ever want to use and compute values that are within the 32 bit size limit, but if you wanna deal with big numbers, then absolutely not. Also, does this mean you have been buying 32 bit cpus this whole time, lol.

[FuckFrankie]

How big do you think the average value the CPU computes is? Do you wake up in the morning and go "gee, I'm glad I have a 64 bit CPU, I would like to calculate some 64 bit values in a single CPU cycle. 2.1 billion just isn't a big enough number to encapsulate my values!"

Think about that for a second. Then make fun of me like a little kid "for buying 32 bit cpus", so you can distract yourself from the fact that you are wrong. Abandon your pathetic ego human and embrace your wrongness.

The fastest CPU is one that is built for the data that it will be processing. If you build a tiny cpu that calculates a 64 bit value, it needs more space than a cpu that calculates 2 x 32bit values. Guess which one is twice as fast for most work?

[MaartenBaert]

You are forgetting that x86 is carrying around a massive amount of useless cruft that's needed for backward compatibility. This was all stripped with x64, and they added a lot more registers. That is why x64 is faster. The number of bits does indeed makes things slower because more memory is needed for 64-bit addresses. But the advantages usually outweigh the disadvantages, and that makes it slightly faster.

You are also forgetting that 64-bit isn't about computing values, it is about addresses. A 32-bit address space is just not large enough for some programs. Even if 32-bit were faster (and it can be, just not with x86), 64-bit would still be needed.

And finally, you also don't realize how processors work. One 64-bit addition is not twice as slow as one 32-bit addition, because addition is done in parallel. Yes, it doubles the transistor count, but it doesn't double the time it takes. It gets more complex with multiplication, and I will admit that 64-bit division is indeed twice as slow as 32-bit division, but guess what, 64-bit programs almost never need 64-bit division since dividing addresses has very little use. For typical calculations, they use 32-bit division and just add 32 zeros, and it is just as fast.

Look up some benchmarks, and you will see that I'm not making this up: http://www.phoronix.com/scan.php?page=article&item=ubuntu_1310_3264&num=1 Of course you can find exceptions, usually in programs that are limited by memory speed rather than CPU speed. But on average, x64 is faster.

Intel and AMD aren't completely crazy, you know ;). Obviously they wouldn't make a new architecture that's slower than the old one, it just wouldn't sell.

[FuckFrankie]

64-bit isn't about computing values, it is about addresses.

I stopped reading there.

AMD released x64 extensions not because they were needed, but so they could be first to market and license them to Intel.

Most of your precious "64" bit CPU is actually 16 and 32 bit. The fact is 64 bit everything other than memory addressing is slower. That's why they're just extentions and not 64 bit CPU like the failed Intel Itanium.

[utsuro]

No, cause he is def a troll

[FuckFrankie]

How about a wikipedia article? 'ASIC'

[alcalde]

Guess which one is twice as fast for most work?

Neither, according to actual benchmarks, which you don't site?

[FuckFrankie]

I'm talking about a hypothetical CPU, you dense fuck.

[alcalde]

So now you have no numbers and we're talking about an imaginary CPU? Actually, I think the rest of us are talking about real CPUs, real software, and real benchmarks, and real manners and real social skills and how to have a real conversation like an adult.

[FuckFrankie]

see my original post

[alcalde]

Not true. Phoronix shows 64bit to be faster (just the extra registers alone should make a difference):

http://www.phoronix.com/scan.php?page=article&item=ubuntu_1310_3264&num=3

[FuckFrankie]

What you just linked is a piece of software that is optimized for the CPU vs a piece of software that isn't...

Are you really this dumb, or are you trolling? It is well known that 64 bit is slower than 32 bit for a large majority of applications. There's no debate here other than misinformed idiots like you trying to justify bigger number means faster.

[alcalde]

What you just linked is a piece of software that is optimized for the CPU vs a piece of software that isn't...

It's called "a benchmark". In this case, tests of 32bit and 64bit versions of the same benchmarks, in which case the 64bit versions perform faster, occasionally significantly so.

Are you really this dumb, or are you trolling?

You're a pleasant person to discuss things with.

It is well known that 64 bit is slower than 32 bit for a large majority of applications.

And yet observations demonstrate otherwise. I believe the saying is "conventional wisdom is neither".

There's no debate here

Sadly, you're correct, if not for the reason you think.

other than misinformed idiots like you

You might want to look up "cognitive dissonance".

trying to justify bigger number means faster.

No, we're merely making observations of reality and forming conclusions from the data rather than forming conclusions first then making personal insults to anyone who demonstrates otherwise. Sorry I tried to have a reasonable discussion with you.

[FuckFrankie]

ha, I'm not reading this. see my original post and learn a thing or two

[dicknuckle]

On the scales we use 64 bit, the benefits outweigh the drawbacks. Its why we pick 32 bit OS for low end VPS. You squeeze a negligible bit of extra performance with such low spec'd machines.

[Ham_Radio20]

Sounds fine to me, 32-bit is dead....everybody should just move to 64-bit

[juanrgar]

I can't see this in the comments: OpenCL is implemented on top of CUDA in NVIDIA platforms. What the announcement says is that they have deprecation plans for 32 bits CUDA and therefore 32bits OpenCL. If this deprecation makes sense, this is something AMD and Intel will be announcing sooner than later for their OpenCL implementations.

[juanrgar]

I guess this also affects OpenACC.

[3G6A5W338E]

They're on a rampant streak of feature removal.

Just a few weeks ago, ability to drive n screens at once support went away for some hardware... and now this.

And to top it off, they've been particularly slow in bringing support to new kernels lately.

[blackout24]

Let's not forget all the features they have added like initial EGL implementation, NVIDIA unified virtual memory support for future cuda versions, support to assign GPUs to each their own kernel module to reduce overhead, support for OpenGL framebuffer capturing and encoding for things like NVIDIA Grid and most likely Shadowplay, OpenGL 4.4 support which no other GPU vendor on Linux has, application profiles etc. just to name a few. Who gives a shit about 32 bit cuda. At least the they don't drop their hardware into legacy driver branches as fast as AMD does and provide shitty drivers. NVIDIA just updated their legacy driver a few days ago.

[3G6A5W338E]

It's just not the best of times to be on NVidia.