Based on watching iStat while the training is running, it seems like larger training jobs aren't really spinning up the GPU much, nor heavily occupying the gpu memory. The jump from a few minutes up to hours of time might be a software related issue rather than necessarily a hardware limitation
I have some additional data points if you're interested:
M1 Max 32 Core (64GB)
torch-1.13.0.dev20220628-cp310-none-macosx_11_0_arm64.whl
Based on watching iStat while the training is running, it seems like larger training jobs aren't really spinning up the GPU much, nor heavily occupying the gpu memory. The jump from a few minutes up to hours of time might be a software related issue rather than necessarily a hardware limitation