Interface: ObserverStats

Defined in: node_modules/footprintjs/dist/types/lib/runner/DeferredObserverTier.d.ts:88

The Block 9 observability surface — snapshot.observerStats. The A4 dispatcher stats plus the terminal-flush stranding count from Block 8. Present on RuntimeSnapshot only when a deferred observer was attached.

Extends

• DispatcherStats

Properties

budgetExhausted

readonly budgetExhausted: number

Defined in: node_modules/footprintjs/dist/types/lib/observer-queue/deferredDispatcher.d.ts:100

Flushes cut short by flushBudgetMs (A1).

Inherited from

DispatcherStats.budgetExhausted

---

depth

readonly depth: number

Defined in: node_modules/footprintjs/dist/types/lib/observer-queue/deferredDispatcher.d.ts:94

Current backlog.

Inherited from

DispatcherStats.depth

---

drops

readonly drops: number

Defined in: node_modules/footprintjs/dist/types/lib/observer-queue/deferredDispatcher.d.ts:96

Events LOST (overflow) — never silent; also visible as seq gaps.

Inherited from

DispatcherStats.drops

---

flushes

readonly flushes: number

Defined in: node_modules/footprintjs/dist/types/lib/observer-queue/deferredDispatcher.d.ts:98

Completed checkpoint flushes.

Inherited from

DispatcherStats.flushes

---

inflight

readonly inflight: number

Defined in: node_modules/footprintjs/dist/types/lib/observer-queue/deferredDispatcher.d.ts:106

Async listener continuations not yet settled.

Inherited from

DispatcherStats.inflight

---

inlineDeliveries

readonly inlineDeliveries: number

Defined in: node_modules/footprintjs/dist/types/lib/observer-queue/deferredDispatcher.d.ts:104

'block'-policy refusals delivered synchronously inline.

Inherited from

DispatcherStats.inlineDeliveries

---

p95FlushMs

readonly p95FlushMs: number

Defined in: node_modules/footprintjs/dist/types/lib/observer-queue/deferredDispatcher.d.ts:102

p95 flush duration, ms (rolling window).

Inherited from

DispatcherStats.p95FlushMs

---

perListener

readonly perListener: Readonly<Record<string, ListenerStats>>

Defined in: node_modules/footprintjs/dist/types/lib/observer-queue/deferredDispatcher.d.ts:108

Per-listener time accounting — "name the hog" (A2).

Inherited from

DispatcherStats.perListener

---

terminalStranded

readonly terminalStranded: number

Defined in: node_modules/footprintjs/dist/types/lib/runner/DeferredObserverTier.d.ts:95

Envelopes still queued when a terminal flush hit its runaway-cascade round cap (Block 8). 0 in any sane run — a non-zero value means a listener kept enqueueing work at end-of-run and delivery was cut off (also dev-warned at the moment it happened). Never silent.