trackedBytes undercounted the packet store by about 2.5x, so packetStore.maxMemoryMB never triggered: a tx was charged at creation, before pickBestObservation set its path, so the byPathHop and spTxIndex costs were never added, and eviction then re-estimated with the path known and subtracted more than had been added, drifting the total downwards. The ParsedDecoded cache, the obsKeys dedup key and several per-observation strings were not estimated at all.
StoreTx.accountedBytes now records what was charged, rechargeTx returns the delta after every pickBestObservation, and eviction subtracts accountedBytes instead of re-estimating. Measured by the author on a production database copy: trackedMB 151 against 402 MB of heap in use before, 351 against 396 MB after, with GC cycles dropping from ~0.71/s to ~0.011/s over 12 h on their instance.
Reviewed by auditing the accounting rather than the arithmetic: all six production pickBestObservation sites recharge, all three subtraction sites read accountedBytes, every recharge site holds s.mu (Load from :857, the two ingest paths at :2778 and :3142 with deferred unlocks), observations are charged only after acceptance, and no charged tx is discarded during the chunk merge. That lock audit is the independent check, because CI's race job covers the ingestor only.
Operator impact, both from the estimate growing rather than any limit moving: where maxMemoryMB is set, eviction now caps the real store size, and the cold load clamp drops about a third of the boot walk (124420 to 84374 packets at 650 MB). Where it is unset, which is the default, the change is inert. docs/go-migration.md claimed the Go server ignored the setting, which was never true, and is corrected here.
Merged by the interim maintainer without a second human reviewer: CI (run 35258839322) plus the review above are the independent checks.
Alex B