英文:
does valgrind support profiling SYCL applications
问题
我正在尝试确定Valgrind对不同编程语言的支持情况，我只想找到Valgrind对SYCL应用程序的支持情况，如果支持，如何分析SYCL应用程序。如果不支持，原因是什么？
我尝试查找与SYCL分析相关的文档，我发现SYCL有自己的分析工具，并找到了一篇关于使用Valgrind调试SYCL的博客，但是我没有找到使用Valgrind进行分析的文档。
英文:
I'm trying to identify valgrind's support for different Programing languages, I just want to find the valgrind's support for the SYCL applications, if supports how to profile the SYCL Application, If not why?
I tried finding the documents related to SYCL profiling and I found that SYCL has its own profiler and also found a blog related to debugging SYCL using Valgrind, but I didn't get the documents related to profiling using Valgrind.
答案1
得分: 1
依赖于SYCL实现和后端/目标设备。
Valgrind不知道加速器上发生的任何事情。因此，在GPU上运行的内核将无法工作。
然而，有一些SYCL实现支持在主机上执行内核，就像常规的C++代码一样。通常称为“仅库”实现，因为在这种情况下，SYCL实现在行为上表现得像常规的C++库。在这种情况下，所有常规的C++调试和性能分析工具，如gdb或valgrind，将像通常一样与应用程序的整体部分一起工作，包括内核代码。
这种模式特别受到hipSYCL/Open SYCL的支持。
如果在GPU上运行，通常来自该GPU后端的本机性能分析和调试工具将起作用。例如，如果通过具有CUDA后端的SYCL实现（如DPC++或hipSYCL/Open SYCL）运行SYCL代码，您将能够使用NVIDIA的工具。这是因为从工具的角度来看，SYCL应用程序看起来和行为都与任何CUDA应用程序一样。
关于“SYCL有自己的性能分析工具”，我不确定您是什么意思。SYCL是一个标准，因此不定义任何调试或性能分析工具。一些SYCL实现可能附带了它们自己的工具。
英文:
It depends on the SYCL implementation and the backend / target device.
Valgrind is not aware of anything that happens on accelerators. So kernels running on GPU won't work.
However, there are SYCL implementations that support executing kernels on the host as regular C++ code. This is usually called "library-only" implementation, because the SYCL implementation behaves like a regular C++ library in this scenario. In that case, all the usual C++ debugging and profiling tools like gdb or valgrind will work as usual with the entirety of the application, including kernel code.
This mode is supported in particular by hipSYCL/Open SYCL.
If you run on GPU, generally the native profiling and debugging tools from that GPU backend will work. For example, if you run your SYCL code through a SYCL implementation with a CUDA backend (such as DPC++ or hipSYCL/Open SYCL), you will be able to use NVIDIA's tools. This is because from the perspective of the tools, the SYCL application looks and behaves just like any CUDA application.
I'm not sure what you mean by "SYCL has its own profiler". SYCL is a standard and as such does not define any debugging or profiling tools. Some SYCL implementations may come with their own tooling.
答案2
得分: 0
不，Valgrind不支持任何形式的分区执行。
在CPU上执行的组件应该可以在Valgrind中运行正常。但Valgrind没有代码来对运行在GPU/FPGA/DSP上的部分进行仪器化。执行模型之间也存在重大的概念差异。在CPU上，Valgrind使用全局锁定并表现得好像只有一个CPU，而GPU是大规模并行的。如果您只能一次使用一个GPU元素，我想它将变得非常慢。
英文:
No, Valgrind doesn't support any form of partitioned execution.
The component that executes on the CPU should be OK to run in Valgrind. But Valgrind contains no code to instrument the part that runs on GPU/FPGA/DSP. There is also a major conceptual difference between the execution models. On CPUs Valgrind runs with a global lock and behaves as if there is just one CPU whilst GPUs are massively parallel. If you could only use one GPU element at a time I imagine that it would be unfeasibly slow.
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论