Expand description
2026-09-26: Telemetry: one instrument set behind one level gate.
Every hot-path entry point first loads one relaxed atomic (the level, or
for kernel_spans_armed the armed flag) and at Off returns before any
clock read, allocation or atomic write. tests/zero_cost_off.rs checks it
with a counting allocator and a counting clock.
The serving process uses global, a static: the HTTP handlers for
/metrics and /v1/events, the GPU backend and the device sampler thread
all reach it without a handle from the scheduler. Tests build their own
instance.
Owner: telemetry.
Invariants: at Off, no hot-path entry point reads the clock, allocates
or writes an atomic.
Structs§
Enums§
- Device
State - 2026-09-26: Whether the device layer is reading.
Constants§
- LIVE_
WINDOW - 2026-09-26: Device samples the live J/token spans (1 s at the serving cadence).
Functions§
- global
- 2026-09-26: The serving process’s instrument set.