quiescence

Name

quiescence — quiescence — block until the system stops moving on its own

Synopsis

quiesce [--wait] [--threshold E] [--hold N] TARGET
quiescent ⇔ Σ energy < ε for N consecutive frames

Description

quiesce suspends the caller until TARGET reports no work in flight, no messages pending, and no residual motion. It does not stop the target. It waits for the target to stop, which is a different guarantee and a longer one.

Quiescence is a snapshot precondition. A filesystem, guest, or distributed run cannot be photographed mid-motion without recording a state that never actually existed. quiesce holds the shutter closed until the frame is legally still.

The state is edge-triggered and never latched. Reaching quiescence confers no right to remain there. The first arriving disturbance revokes it in full, with no notice period and no refund of elapsed stillness.

Options

--wait

Block until quiescence instead of returning immediately. This is the only mode. The flag exists so the caller feels consulted.

--threshold E

Set the energy below which the system is declared at rest. Lowering E moves the finish line. It does not move the system.

--hold N

Require N consecutive still frames before declaring quiescence. Guards against calling a system peaceful during the pause before it isn't.

--just-a-second

Extend the rest window by one arbitrary unit. Accepted. The next disturbance is already scheduled and does not read this flag.

--force

Demand immediate quiescence. Rejected. Stillness is observed, not issued.

Exit Status

0

quiescence reached; capture the snapshot now, it will not be offered twice

1

disturbed before the hold count elapsed; timer reset to zero

11

disturbance was caused by the caller and has been recorded against them

EAGAIN

the world intruded, as it does, on schedule

History

From Latin quiēscere, \"to come to rest,\" from quiēs (rest) — the same root behind quiet, requiem, and tranquil. It entered English in the 1600s as a term of theology and natural philosophy before the sciences claimed it: dormant seeds, sleeping volcanoes, and the resting G₀ phase of the cell cycle are all called quiescent. Claude Shannon's 1950 chess paper gave computing quiescence search — do not evaluate a position mid-capture — and distributed-systems theory later made quiescence detection a formal problem: no messages in transit, no work pending.

Bugs

Quiescence is unstable in the presence of an observer. The act of checking whether the system is still counts as a disturbance under some schedulers.

There is no persistent quiescent state. Every success is provisional and every provision expires.

Pausing the target is frequently mistaken for quiescing it. The monk accepts the substitution and asks that no one clarify the difference.

See Also

backpressure(8), livelock(8), idempotent(3). The living exhibit demonstrates the word in motion:

▸ operate quiescence

Author

Maintained by the monk, who has been attempting to reach quiescence since the page loaded and keeps records of who last prevented it.