http://www.k-wave.org/forum/topic/c-fft-plans-creation-really-slow Support for the k-Wave MATLAB toolbox en-US Tue, 12 May 2026 22:25:12 +0000 http://bbpress.org/?v=1.0.2 q http://www.k-wave.org/forum/search.php http://www.k-wave.org/forum/topic/c-fft-plans-creation-really-slow#post-9092 Thu, 09 May 2024 16:08:22 +0000 zak morgan 9092@http://www.k-wave.org/forum/ <p>Never mind, I was ecperimeting with PML and had it set to be outside the grid, thus growing the grid to a non-power of 2 size thus explaining the slow-down! </p> http://www.k-wave.org/forum/topic/c-fft-plans-creation-really-slow#post-9091 Thu, 09 May 2024 00:09:21 +0000 zak morgan 9091@http://www.k-wave.org/forum/ <p>I'm also seeing similar, when running on the CPU c++ code pre-pocessing is instant and then my simulation takes about 47 seconds, however when running the CUDA code, the simulation takes about 10 seconds, but 80 seconds is spent on pre-processing the FFT. It seems odd that preprocessing should be this much slower on the GPU than on the CPU? </p> http://www.k-wave.org/forum/topic/c-fft-plans-creation-really-slow#post-8794 Tue, 06 Jun 2023 12:58:24 +0000 Jiri Jaros 8794@http://www.k-wave.org/forum/ <p>is the GPU set into PM mode 1? </p> <p>sudo nvidia-smi -pm 1</p> <p>It is also an extremely small simulation, so I'm not sure what it does. It may also do something odd in the preporessing phase. </p> http://www.k-wave.org/forum/topic/c-fft-plans-creation-really-slow#post-8560 Tue, 05 Jul 2022 22:54:06 +0000 tnie 8560@http://www.k-wave.org/forum/ <p>Simulating a trivial example, the <code>FFT plans creation</code> phase takes 126.52 seconds while the simulation itself takes less than a second. That can't be right... The same simulation runs in less than a second total in MATLAB. </p> <p>I get the following output</p> <pre><code>+---------------------------------------------------------------+ | kspaceFirstOrder-CUDA v1.3 | +---------------------------------------------------------------+ | Reading simulation configuration: Done | | Selected GPU device id: 0 | | GPU device name: NVIDIA GeForce RTX 3090 | | Number of CPU threads: 1 | | Processor name: Intel(R) Core(TM) i7-10700K CPU @ 3.80GHz | +---------------------------------------------------------------+ | Simulation details | +---------------------------------------------------------------+ | Domain dimensions: 128 x 108 | | Medium type: 2D | | Simulation time steps: 793 | +---------------------------------------------------------------+ | Initialization | +---------------------------------------------------------------+ | Memory allocation: Done | | Data loading: Done | | Elapsed time: 0.01s | +---------------------------------------------------------------+ | FFT plans creation: Done | | Pre-processing phase: Done | | Elapsed time: 126.52s | +---------------------------------------------------------------+ | Computational resources | +---------------------------------------------------------------+ | Current host memory in use: 408MB | | Current device memory in use: 1300MB | | Expected output file size: 0MB | +---------------------------------------------------------------+ | Simulation | +----------+----------------+--------------+--------------------+ | Progress | Elapsed time | Time to go | Est. finish time | +----------+----------------+--------------+--------------------+ | 0% | 0.001s | 0.396s | 05/07/22 16:52:22 | | 5% | 0.014s | 0.257s | 05/07/22 16:52:22 | | 10% | 0.029s | 0.255s | 05/07/22 16:52:22 | | 15% | 0.044s | 0.247s | 05/07/22 16:52:22 | | 20% | 0.058s | 0.229s | 05/07/22 16:52:22 | | 25% | 0.071s | 0.211s | 05/07/22 16:52:22 | | 30% | 0.086s | 0.199s | 05/07/22 16:52:22 | | 35% | 0.100s | 0.184s | 05/07/22 16:52:22 | | 40% | 0.114s | 0.169s | 05/07/22 16:52:22 | | 45% | 0.130s | 0.158s | 05/07/22 16:52:22 | | 50% | 0.143s | 0.142s | 05/07/22 16:52:22 | | 55% | 0.159s | 0.129s | 05/07/22 16:52:22 | | 60% | 0.173s | 0.115s | 05/07/22 16:52:22 | | 65% | 0.185s | 0.099s | 05/07/22 16:52:22 | | 70% | 0.203s | 0.086s | 05/07/22 16:52:22 | | 75% | 0.217s | 0.072s | 05/07/22 16:52:22 | | 80% | 0.231s | 0.057s | 05/07/22 16:52:22 | | 85% | 0.245s | 0.042s | 05/07/22 16:52:22 | | 90% | 0.259s | 0.028s | 05/07/22 16:52:22 | | 95% | 0.273s | 0.014s | 05/07/22 16:52:22 | +----------+----------------+--------------+--------------------+ | Elapsed time: 0.29s | +---------------------------------------------------------------+ | Sampled data post-processing: Done | | Elapsed time: 0.01s | +---------------------------------------------------------------+ | Summary | +---------------------------------------------------------------+ | Peak host memory in use: 408MB | | Peak device memory in use: 1300MB | +---------------------------------------------------------------+ | Total execution time: 128.07s | +---------------------------------------------------------------+ | End of computation | +---------------------------------------------------------------+</code></pre> <p>Any idea how to make the C++ binary faster? </p>