Scheduler Switch

Want to A/B two schedulers without editing your sampler's widgets every run? Scheduler Switch is the two-way switch from RvTools v2's switch family, pointed at scheduler values: wire a scheduler from one source into input1, another into input2, and the Input integer (1 or 2) decides which one comes out the scheduler output. It's one of the rare RvTools switches that isn't deprecated - it lives in the active Switches category.

How it works

The mechanism is shared with every switch in the pack, and the README spells it out: when the node is bypassed, it sends whatever is connected to input1 to the target; when enabled, Input (1 or 2) picks the slot. The inputs are typed as * (any) so they'll accept a scheduler string from any source - a vanilla KSampler-style wire, another selector, even a text node if you want to type a scheduler name. The output socket is typed to the vanilla ComfyUI scheduler list (simple, sgm_uniform, karras, exponential, ddim_uniform, beta, normal, linear_quadratic, kl_optimal), which is what a vanilla KSampler scheduler input accepts.

The inputs that matter

• Input (INT, 1 or 2) - the selector. Default 1.
• input1 / input2 (*) - the two scheduler candidates.

That's it. No logic, no blending, just if Input == 1: return input1 else return input2. Which means you can drive Input from any integer source - a slider, another node, a loop counter - and change schedulers per batch without touching the graph.

Why you'd bother

Schedulers are a real quality lever: karras gives a classic curve, exponential is the go-to for many Flux workflows, and AYS presets are tuned for specific model families. Being able to switch them at runtime - or bypass the switch entirely and fall back to input1 - makes scheduler A/B testing a one-knob affair instead of a widget-editing exercise. If your sampler's scheduler is a widget (vanilla KSampler), you'll need a selector node to get a scheduler value onto a wire first; this switch then picks between two of those wires.

Installing it

ComfyUI Manager → search ComfyUI-RvTools_v2, install, restart; or:

cd ComfyUI/custom_nodes
git clone https://github.com/r-vage/ComfyUI-RvTools_v2

No model downloads, no extra deps.

Gotchas

Two things. The output socket is typed to the vanilla scheduler list, so if you feed it a scheduler outside that list (say GITS[coeff=1.2] from the Impact list), ComfyUI's type checker may refuse the connection or the wire may not validate - for those, grab the Impact/Efficient/Restart variants of this same switch, which have widened sockets. And remember the v2 rename: legacy ComfyUI-RvTools v1 workflows won't match these node names, so Manager reports them missing. The pack itself is unmaintained (superseded by ComfyUI_Eclipse) but switches like this are simple enough to keep working forever.