Commit Graph
3 Commits
Author SHA1 Message Date
bvandeusenandClaude Opus 5 45bb7044f7 feat: the System tab reads a stored sample instead of inspecting per load (4295)
CI and images / lint (push) Failing after 3s
CI and images / extension-version (push) Successful in 4s
CI and images / frontend-build (push) Successful in 31s
CI and images / backend-lint-and-test (push) Successful in 35s
CI and images / integration (push) Successful in 2m44s
CI and images / sign-extension (push) Skipped
CI and images / build-web (push) Skipped
CI and images / smoke-web (push) Skipped
CI and images / promote (push) Skipped
CI and images / build-agent (push) Skipped
Operator: "there is a repull every time this page loads is there a reason
this info isn't being tracked in the background and stored in some way?"

There was a reason and it had expired, and underneath it there was plain
waste.

The expired one: /api/system/workers was deliberately uncached because an
operator dragging the stepper must not be shown a pre-change value. That
stopped being true at 1353d34, when the UI began patching its row from the
write's reply instead of refetching.

The waste: size_worker_lanes already inspected the broker on a timer to
decide pool sizes — computing the pool, active, reserved and queue depth
the page shows, using them, and discarding them. The browser then asked
the broker for the same numbers four times a minute, per open tab.

So one inspect now feeds three things: the sizing decision, a stored
sample (worker_lane_sample, alembic 0107), and the celery roster. No
request path touches the broker at all — the roster refresh comes off
/api/system/health too, where it had been rate-limited to 20s and so made
worker liveness a function of whether anyone had a browser open.

Consequences, stated rather than hidden:

- The live figures are up to one sweep old. measured_at travels with each
  lane and the page says how old, because a stale number presented as
  current is how someone watches a queue "not move" that is moving.
- The sweep is the roster's only writer now, so its period and the
  staleness thresholds are in a relationship. 60s against a 90s stale
  threshold left one missed tick between normal and all-yellow — the
  shape of lesson #4355 — so the period is 30s, named once in
  worker_lanes, and system_health asserts its headroom at import with a
  test stating the same thing in prose.
- An idle lane therefore also gives a worker back twice as fast. That is
  the direction asked for: "idle instances quiet down when not running".

Also bounds the inspect in push_lane_cap, which was an await with no
deadline (rule 156) — harmless while it ran on a request, less so now
that it runs in a background task where a hang would be silent.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LVjrnpQjRgHdvq95rASoiR
2026-09-23 18:52:08 -04:00
bvandeusenandClaude Opus 5 445164c852 feat: one number per lane — the cap — and the autoscaler is the mechanism (4295)
CI and images / lint (push) Successful in 4s
CI and images / extension-version (push) Successful in 4s
CI and images / frontend-build (push) Successful in 24s
CI and images / integration (push) Failing after 24s
CI and images / backend-lint-and-test (push) Failing after 34s
CI and images / sign-extension (push) Skipped
CI and images / build-web (push) Skipped
CI and images / smoke-web (push) Skipped
CI and images / promote (push) Skipped
CI and images / build-agent (push) Skipped
Operator, 2026-09-23: *"auto should be always on, not a setting, so that idle
instances quiet down when not running. the number that is visible and
something the user can tweak and manage should be the cap itself the number of
running workers is handled by the autoscaling function which is always on."*

They are right, and the reason it was not built this way is worth stating: the
manual dial came first (steps 2-4) and the autoscaler came last (step 7), as
an opt-in BESIDE a control that already existed. Nothing ever asked whether
the dial should still exist once something could move it automatically. Each
step was defensible; the result was three operator settings over one number.

## `slots`, `enabled` and `autoscale` are gone

`slots` was a MEASUREMENT wearing a preference's clothes. How many workers a
lane runs is read live and moved every minute; storing it meant the operator
had to keep two numbers in agreement and the autoscaler had to be told it was
allowed to touch one of them.

`autoscale` gated the mechanism behind a choice, so a lane nobody opted in
never gave its workers back — which is why an idle instance never quieted
down.

`enabled` is derived: a cap of zero means no consumers. "Off" and "may use no
workers" were two spellings of one fact, stored separately, free to disagree.

## Two sweeps become one

`reconcile_lanes_sync` drove the pool to the stored `slots`; `autoscale_lanes_
sync` moved it away from that same number; and most of step 7's hardest
reasoning — a stored value that is a FLOOR, a target of `max(stored, current)`
— existed only to stop them fighting. Delete the stored number and the problem
is not solved, it is absent.

`size_lanes_sync` runs every minute and owns both consumers and pool size. It
also subsumes what the reconcile was for: a worker restarted at its ENV
concurrency is corrected on the next tick rather than after five.

Growth is immediate, shrink is one worker per tick. Deliberately asymmetric —
"always on" is only pleasant if the ramp keeps up, and +1/minute would take
four minutes to answer a burst. Being one worker too large for a minute costs
a sleeping process; being too small costs work not happening. For ML the
asymmetry matters most: every new slot reloads a multi-GB model, so the slow
shrink is what stops a quiet patch from paying that cost again a minute later.

## The caps ship at one, and zero for ML

Per the operator. Conservative on purpose — and a conservative default nobody
knows how to raise is just a slow product, which is the other half of what
they asked for:

    "there needs to be something that tells the user to bump those numbers to
     improve processing rate or they'd never know the controls exist."

So a lane running everything its cap allows while work piles up says so, in
its own row, with the headroom named: *"4,060 waiting and all 1 worker busy.
Raise the cap to run more at once — this machine allows up to 7."*

It fires only when raising the cap would actually help. Not when the lane is
keeping up, not when the sizing pass has room it has not taken, and not at the
machine ceiling — where "raise the cap" is advice nobody can take.

## Migration 0105 rewrites the caps rather than carrying them

The old defaults (4/2/2/1) bounded a manual control and were loose because
moving within them was the ordinary act. The number now means "the most
workers this lane may use", which is a different promise; carrying the old
figure over would quadruple the worker lane on every existing install at the
moment this deploys.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LVjrnpQjRgHdvq95rASoiR
2026-09-23 12:48:22 -04:00
bvandeusenandClaude Opus 5 abe16aa382 feat: the System tab is one bounded table, and the dial is the switch (4295)
CI and images / frontend-build (push) Successful in 20s
CI and images / backend-lint-and-test (push) Successful in 32s
CI and images / lint (push) Successful in 3s
CI and images / extension-version (push) Successful in 3s
CI and images / integration (push) Successful in 2m10s
CI and images / sign-extension (push) Successful in 3s
CI and images / build-agent (push) Successful in 6s
CI and images / build-web (push) Successful in 2m10s
CI and images / smoke-web (push) Successful in 52s
CI and images / promote (push) Skipped
Operator, 2026-09-23, on the screenshot: *"I feel that we can probably combine
the two sections into a single table and to format it in such a way that it
appears more bounded and less free-form or open. also there's nothing to
describe what 'auto' means or why their needs to be or should be on/off
toggles. almost all of it always needs to run there's only one optional piece
and it is killed by moving the 'cap' to zero."*

Three separate things, all correct.

## The four lanes were listed twice

The roster (milestone 365) said "ML tagging is running", and four hundred
pixels below it the lanes pane said "ML tagging · 1/1 busy". Two answers to
one question from two endpoints, free to disagree on screen. I moved the
second pane onto this tab yesterday and did not notice it duplicated the
first.

Now one row per part, with controls on the rows that have a lane and none on
the rows that do not. The join is on the QUEUE SET, because that is what
`service_roster` keys a celery part on — as a set, not as a string, so neither
side has to agree about order.

It lives in `utils/systemParts.js` rather than inline, and has a spec, because
its failure is SILENT and is the exact thing it exists to prevent: a lane that
stops matching its part does not throw, it grows a second row for the same
worker. The duplication, returning through the code that removed it.

## Bounded, not free-form

A real table — header, column rules, one bordered card — instead of dotted
rows floating on the page background with nothing saying where the list began
or what a column meant.

## The dial is the switch

There was an `On` switch per lane beside the slots dial. Of four lanes, three
must run for the application to work at all, so that switch offered a choice
that was never real — and for the one lane that IS optional, "off" and "zero
slots" were two ways of saying the same thing that could disagree with each
other.

So `enabled` is now DERIVED from the number: `set_lane` sets it from
`slots > 0` when the caller did not say. It stays on the API and in the model
— it is still the mechanism, and a drain-before-restart may still want a lane
holding its process with consumers cancelled without destroying the operator's
slot count to say so.

Two things fell out that a test now pins:

- The consumer command is sent on the CHANGE, not on the field being present.
  Otherwise every slots write re-sends a command that changes nothing —
  lesson #4183's churn, arriving through the new derivation.
- The model fetch fires on the off→on TRANSITION. It used to test `enabled is
  True`, the field having been sent. The UI no longer sends it, so the
  download that makes the ML lane usable would simply never have fired and the
  lane would have come on to consume a queue it had no model for.

## And Auto now says what it is

A legend under the table, in the operator's terms: what a slot is, that zero
turns a lane off, that three of the four are not optional, what `of N` means,
and that Auto lets a lane add slots by itself when its queue is backed up AND
every slot is busy — with why it is off by default, since it is the only thing
on the page that acts without being asked.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LVjrnpQjRgHdvq95rASoiR
2026-09-23 11:26:27 -04:00