2 ms·
MoE's still require the total number of parameters (46b, not 56b, there's some overlap) to be in ram/vram, but the benefit is that the inference speed will be b
by 0tfoaij 2y ago
MoE's still require the total number of parameters (46b, not 56b, there's some overlap) to be in ram/vram, but the benefit is that the inference speed will be based on the amount of active parameters used, which in the case of Mixtral is 2 experts at 7b each for an inference speed comparable to 14b dense models. This 3x improvement in inference speed would be worth the additional ram usage alone, especially for cpu inference where memory bandwidth rather than total memory capacity is the limiting factor, but as a bonus there's a general rule you can use calculate how well MoE's will compare to dense models by taking the square root of the active parameters * total parameters, meaning Mixtral ends up comparing favourably to 25b dense models for example. In the case of ARIA it's going to have the memory usage of a 25b model, with the performance of a 10b~ model while running as fast as a 4b model. This is a nice trade off to make if you can spare the additional ram.
If it helps, MoE's aren't just disparate 'expert' models trained to deal with specific domain knowledge jammed into a bigger model, but rather are the same base model trained in similar ways where each model ends up specialising on individual tokens. As the image dartos linked shows, you can end up with some 'experts' in the model that really, really like placing punctuation or language syntax for whatever reason.