Timer Start (CCN)

Timer Start (CCN) does exactly one thing: it stamps the current wall-clock time and hands it out. No inputs, no settings, a single start_time FLOAT output. It is the most boring node you'll ever wire, and that's the point - it's one half of a two-node stopwatch, designed to be paired with Timer Stop (CCN).

Why would you want a stopwatch in a ComfyUI workflow at all? Because "this workflow feels slow" is not a diagnosis. Drop Timer Start upstream of the stage you're curious about - the encode, the first KSampler pass, the upscale - and Timer Stop downstream of it, and you get an actual number instead of a vibe. The classic use is timing individual stages of a multi-pass generation, or checking whether a new node you added is actually costing you seconds. It turns performance complaints into measurements you can act on.

How it works

At execution time it captures time.time() - a Unix epoch float - and outputs it as start_time. That's the entire mechanism. The intelligence lives in its partner node, Timer Stop, which subtracts its own timestamp and formats the difference. Timer Start is deliberately dumb so the pair has a single clear contract: one timestamp in, one elapsed time out.

Because the output is just a plain FLOAT, you can also wire it anywhere else you'd want a current timestamp - into a filename builder for a run-time-stamped save path, for example. It doesn't care what you do with it.

The input and output that matter

There are no inputs. The only output is start_time (FLOAT) - feed it to a Timer Stop's start_time input. If you want to measure something, place this node before the work you're timing.

How to install it

Same pack as everything CCN: ComfyUI Manager → search ComfyCollectorNodes → Install, or:

cd ComfyUI/custom_nodes
git clone https://github.com/valkymaera/ComfyCollectorNodes.git

Restart ComfyUI. No extra Python dependencies.

One thing to know

Timer nodes live in the pack's wip/ folder, which the author excludes from the published registry package but keeps in the git repo. In practice that means: if you install via ComfyUI Manager (which git-clones), you'll see them; if they're ever missing after a registry-based install, clone the repo manually and they'll appear. It's the kind of small quirk that only bites someone who installs from the wrong source, and it's worth knowing it exists before you blame the node.