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Comment by Raphael_Amiard | Hacker News Reader

> it will make life a lot better for CUDA programming too

Well having done quite a bit of CUDA programming under Windows and Linux, i'm interested in knowing what you find lacking on Linux ?

Performance wise i can report CUDA is just as fast on Linux as it is on windows.

Regarding tool support, i actually prefer to work under Linux, not because tools are better per se, but because your usual Unix tool chain does wonders with C++/CUDA. Under windows you have to struggle with Visual Studio just to get syntax highlighting.

There seems to be the profiler that is windows only. I never used it so i can't report on that.

EDIT : More generally, i've always found NVIDIA driver support for Linux to be very solid. Of course, it's closed source, but then so it is on Windows. I've never had a problem with an NVIDIA card on Linux, and i can't say that much about AMD/ATI.

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> More generally, i've always found NVIDIA driver support for Linux to be very solid.

I guess you haven't had any laptop with the Optimus technology (NVIDIA dedicated card + Intel integrated GPU). There no official NVIDIA Optimus support for Linux whatsoever :(

Not entirely Nvidia's fault apparently: http://en.wikipedia.org/wiki/Nvidia_Optimus#GPL_blob_buffer-... (though obviously it's their fault for using a proprietary blob)

> (though obviously it's their fault for using a proprietary blob)

I couldn't agree more. The problem with these news sites [1] is that they make the kernel developers look like stubborn zealots that refuse to do something that would ultimately benefit the users, when in fact they aren't really doing anything wrong. The news sites fail to mention the root of this problem: nVidia, a hardware manufacturer, refuses to open source their drivers. This may sound like no big deal; after all, lots of IT companies do that, right?. But it is a big deal. Refusing to open source the drivers is in fact refusing to let the users have control over the their hardware. It's not an end-user application that you can choose not to use; it's the thing that controls the hardware you own. "You can use it, but only through this restricted interface we give you, you can't look inside!". Not a nice move in my books.

[1]: http://www.phoronix.com/scan.php?page=news_item&px=MTA0O...

There is unofficial support, though! Bumblebee was fairly easy for me to set up, and works quite well (again, for me): http://bumblebee-project.org

Yes, Bumblebee is really cool.

My main problem with the Optimus configuration on Linux was overheating: as the discrete card (nVidia) was always on, even if the system wasn't using it, the computer was hotter. Without workload, the normal temperature on Linux was around 53ºC, while on Windows was 42ºC. It felt warmer on the keyboard too.

I had some problems trying to get Bumblebee to work on Fedora (at least the bbswitch worked, so the discrete nVidia card could be turned off, and then the computer wouldn't overheat on Linux). On Ubuntu though, the setup was really smooth [1]: just adding a PPA and then installing a package and everything was working :D

However, while Bumblebee is really cool, it still can't do what the official nVidia and Intel drivers do on Windows. You can run programs in the discrete card with Bumblebee, but you have to use a special command for that (optirun), the cards won't be switched on-the-fly depending on how much processing power is needed, which is the case with the official drivers on Windows. There supposedly is some progress in that regard though [2], in a project called Prime (awesome pun indeed)

[1]: This answer helped a lot too: http://askubuntu.com/questions/36930/how-well-do-laptops-wit... [2]: Blueprints: https://blueprints.launchpad.net/ubuntu/+spec/desktop-r-hybr...

Nvidia support on Linux has been primarily focused on the commercial applications (e.g. rendering farms) and not so much on consumer uses.

I've had some problems with the drivers, which is what I was referring to. Sometimes the computer will get into an unusable state and I don't know why.

There are also some odd issues with the tools. Did you know that CUDA-GDB will give an internal driver error if it can't write to /tmp? No description of what's wrong, just "internal driver error". That one took a while to figure out (and I wasn't the one who figured it out in the end).

I've never really programmed under Windows, so I don't know about the tool support, but I'm very happy with Linux development tools. I have actually used the Nvidia profiler under Linux, but I haven't figured out how to make it give me useful information.

> Performance wise i can report CUDA is just as fast on Linux as it is on windows.

Great. But definitely not the case for OpenGL last I checked (which admittedly is half a year ago).

> There seems to be the profiler that is windows only. I never used it so i can't report on that.

You mean nvvp? Idk about earlier versions but it ships with CUDA 5 for Linux. I've used it too, works just dandy :)

Edit - Beaten to it by "gosu"

> There seems to be the profiler that is windows only. I never used it so i can't report on that.

nvvp? It works for me on Linux.

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