Module cache 

The warm caches runner containers share and keep between jobs: each profile’s read-only snapshot, each slot’s volume (its layers’ changes and its Docker Engine’s data), the shared pnpm store and Maven repository, and the Docker Hub mirror on the runners’ network. Owns their names, mounts and lifecycle; it never decides when a runner starts, and it never touches a volume a running container uses.

Structs

Emptied

A shared cache trim_shared emptied.

Names

The names of everything runnerd creates in Docker, under one prefix: runnerd, or another for tests.

Refused

A volume trim_shared was to remove that Docker refused to.

Reseed

What reseed runs on: the profile’s image and limits, its slots and the isolation backend.

Trimmed

What trim_shared measured and emptied.

Enums

Mirror

Whether the mirror’s container is down, so its storage can be removed.

Constants

MIRROR_IMAGE

The Docker Hub pull-through cache (registry 3.1.2, multi-platform index).

Functions

docker_budget_gib

One slot’s share of disk among slots, in whole GiB as image/layers.sh takes it: at least 1, at most DOCKER_SLOT_MAX_GIB.

docker_disk

What the slots’ Docker Engines may keep together, in bytes: a quarter of Docker’s disk not otherwise used, which is what is free plus what the slot volumes already hold, measured together (docs/adr/0054).

finish_reseed

Waits for a seed container to exit, removes it, and returns its output. Also takes over a seed container an earlier daemon left running: stopping it between its rm and mv would lose that snapshot layer.

mirror_body

The mirror container: Docker Hub through a proxy registry, which refuses pushes, so a job can only make it fetch what Docker Hub serves. Content not pulled again within the TTL expires. No published port.

mirror_down

Stops the mirror; its storage stays.

mirror_up

Starts the mirror unless it runs.

prepare

Creates what a profile’s runner in slot (1-based) mounts and joins, if missing.

reseed

Makes slot 1’s layers the profile’s new snapshot and drops every slot’s own layer changes (image/seed.sh), if slot 1 changed at least min_changes. A snapshot that would outgrow max_size starts over from the image, as every slot’s changes go too (docs/adr/0065); after a reseed that did not finish, it starts over whatever the limits (docs/adr/0066). Call only while none of the profile’s slots runs. Returns the seed container’s output.

runner_mounts

What a runner container in slot slot (1-based) of the profile mounts (paths from image/Dockerfile).

trim_shared

Empties the shared caches that outgrew their limit, the mirror’s storage among them once the mirror is down (Mirror::Down), and removes the volumes of slots past the count slots gives their profile, as a lowered count leaves them: each holds a slot’s layers and Docker store, which no job prunes again (docs/adr/0054). Call only while no runner runs, and leave out of slots a profile whose reseed runs, which mounts its slots’ volumes.

volumes

Every cache volume the config’s profiles use, what it holds and its limit, with size 0.