SamplerLMS_motorway_edition

Let's be honest about LMS: it's a legacy sampler, and it's mostly here because the pack clones every built-in node, not because anyone is demanding it. SamplerLMS_motorway_edition is a clone of ComfyUI's SamplerLMS - a linear multi-step sampler that goes back to the early Stable Diffusion days. It works, it converges, and it was genuinely important once. But against the modern roster - DPM++ 2M, Euler, the SDE family - it doesn't bring anything to the party, and the community moved on years ago. If you found this node by googling, you're probably inheriting an old workflow that never got updated.

That's not to say it's broken. LMS is a converging sampler: give it enough steps and it settles into a stable image, same seed → same result. Its linear-multistep math smooths the trajectory using several past steps, which is why it's decent at moderate step counts and never spectacular. The one knob:

• order (default 4, 1–100) - the number of previous steps the multistep predictor uses. Higher order means more history in the estimate; 4 is the classic default and almost never worth touching.

Like every node in this pack, it's a sampler factory - model in, SAMPLER out, for SamplerCustom's sampler port. If you're rebuilding an old SD 1.5 workflow that specified LMS, know that swapping in DPM++ 2M or Euler at the same step count will almost always look better for free.

What it does on the Motorway

A generated *_motorway_edition clone from ComfyUI_agilly1989_motorway. The pack's idea is a named-key data bus - the Motorway - where values ride under typed key names instead of wires. MotorwayStart starts a bus, Motorway AxB ramps store and fetch keys, and every motorway-edition node pulls its inputs from the bus by key and writes its outputs back by key, always returning the bus. The model comes in via the family's INPUT_…_key convention (default model), and the sampler is parked back under your OUTPUT_SAMPLER_key (default SAMPLER).

Installing it

Part of ComfyUI_agilly1989_motorway. ComfyUI Manager: search ComfyUI_agilly1989_motorway, install, restart. Or:

cd ComfyUI/custom_nodes
git clone https://github.com/agilly1989/ComfyUI_agilly1989_motorway

No extra dependencies, no model files.

The catch

Same as every sibling node: release 1.1.7 ships with the clones switched off, so uncomment the two ClonedNodeMapping lines in custom_nodes/ComfyUI_agilly1989_motorway/__init__.py and restart to see it. And this being a beta from a solo dev, the README's first line - "BIG BROKEN WITH ASYNC WILL FIX WHEN I GET THE TIME/MOTIVATION" - is worth taking at face value. If you're reaching for LMS out of habit, this is a fine place to interrogate that habit; if you're reaching for it because a workflow demands it, at least you now know it's not the sampler that's making the workflow good.