Function evictOldestEvents

src/utils/telemetry/perfettoTracing.ts:232–247

* Drop the oldest half of events[] when over MAX_EVENTS. Called from the * stale-span cleanup interval (60s). The half-batch splice keeps this * amortized O(1) — we don't pay splice cost per-push. A synthetic marker * is inserted so the gap is visible in ui.perfetto.dev.

()

 * is inserted so the gap is visible in ui.perfetto.dev.
 */
function evictOldestEvents(): void {
  if (events.length < MAX_EVENTS) return
  const dropped = events.splice(0, MAX_EVENTS / 2)
  events.unshift({
    name: 'trace_truncated',
    cat: '__metadata',
    ph: 'i',
    ts: dropped[dropped.length - 1]?.ts ?? 0,
    pid: 1,
    tid: 0,
    args: { dropped_events: dropped.length },
  })
  logForDebugging(
    `[Perfetto] Evicted ${dropped.length} oldest events (cap ${MAX_EVENTS})`,
  )
}

/**
 * Initialize Perfetto tracing