Can I use GPU computing inside of a parfor loop?
显示 更早的评论
I am in the process of upgrading my computer and I am wondering if there is a potential for upgrading my GPU. Right now I am only using parfor. However, within the parfor loop there are operations that would seem to benefit from using GPU computing. I get the impression from this entry ( https://www.mathworks.com/matlabcentral/answers/36235-parfor-on-gpu ) that for what I want to do, I would need to use multiple GPUs. Now, I don't know enough about GPUs to know what kind of questions to ask, but I'll start with these:
If I am running 8 workers with parfor, does this mean that I would need to allocate 8 GPUs? Does GPU = graphics card and if so, then I need to buy 8 graphics cards (impractical)? Or do graphics cards have multiple GPUs? If this is possible, how would I go about choosing the right graphics card for the job?
Thanks in advance -jz
采纳的回答
Edric Ellis
2014-3-7
2 个投票
You do not need 8 separate graphics cards even if you have 8 workers using gpuArrays simultaneously. (In fact, I'm not even sure that you can put 8 GPUs in a single system). Having multiple workers using a single GPU simultaneously is called "oversubscribing". Whether or not you see any performance benefit from this depends strongly on the details of your problem - and how much of that you can actually run on the GPU.
For example, consider a case where you have a problem that, when run in a single MATLAB session, only spends 1/4 of its time using the GPU. In that case, you might expect good performance running 4 workers accessing the same GPU (providing the arrays all still fit in memory). If you run that against 8 workers, you will see diminishing returns as the workers all contend for access to the GPU.
4 个评论
Jay
2014-3-7
Edric Ellis
2014-3-7
Actually, MATLAB isn't involved in serialising the requests - CUDA / the GPU does this automatically.
Jay
2014-3-7
Edric Ellis
2014-3-10
You could take a look at the GPUBench results. Generally speaking, NVIDIA's 'Tesla' series of cards are aimed more at computation and usually have better double-precision performance, as well as features like error correction (ECC). The 'GTX' cards often have very good single-precision performance.
更多回答（1 个）
I get the impression from this entry ( https://www.mathworks.com/matlabcentral/answers/36235-parfor-on-gpu ) that for what I want to do, I would need to use multiple GPUs.
That's not the impression I get. Edric said in that thread that 1 GPU (he uses "GPU" to mean graphics card) might be enough, depending on the computation that you're doing. Have you tried it on your current graphics card?
类别
在 帮助中心 和 File Exchange 中查找有关 Parallel for-Loops (parfor) 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
