FSampler (fsampler) is a training-free, sampler-agnostic acceleration layer for diffusion sampling that reduces model calls by predicting each step's epsilon (noise) from recent real calls. Provides fixed history modes (h2/h3/h4) and adaptive mode for 40-60%+ speedup.
https://github.com/obisin/ComfyUI-FSampler
git clone https://github.com/obisin/ComfyUI-FSampler
comfy node install comfyui-FSampler