GPU version of FDK and OS-SART running abnormally

[mysummer123]

Dear author, hello. I would like to ask if my dataset is a projection of 360 CBCTs with a detector size of 972 * 768 pixels. It takes me over 30 seconds to reconstruct using the GPU version of FDK and half an hour using the GPU version of OS SAR. I feel that the reconstruction time is a bit too long, and my GPU usage during the reconstruction process is very strange. It's not always high load, but fluctuating high and low. I also noticed that shared GPU memory is used, which I have never seen before (as shown in the picture). Is there a problem with the settings. The CPU is AMD RYZEN 8845H, and the GPU is the laptop version 4060 (8GB of video memory).
My settings for the GPU code are as follows:

targetGpuName=''
gpuids = gpu.getGpuIds(targetGpuName)
.................
imgFDK = algs.fdk(projs, geo, angles , gpuids=gpuids)
................
imgOSSART = algs.ossart(
projs,
geo,
angles,
niter,
blocksize=blocksize,
OrderStrategy="random",
gpuids=gpuids
)

[AnderBiguri]

Thos graphs are not super informative in general, don't trust them too much. But indeed, I see no issue here. Id the recon is very big, the gou may be splitting the problem in pieces, and in any case, it will use shared memory for computational efficiency. depends on the size of the volume, 30s for FDK and much longer for OS-SART is expected. Given the only operators in GPU are forward/backprojections, your GPU usage seems reasonable

[mysummer123]

Thank you very much for your detailed explanation. It has been of great help to me.