Registry.Meter is reference counted: every call takes a reference, including calls
that find the meter already present, and only Dispose releases one. The enforcers
resolved a meter inside Run, so each run took a reference it never shed. Disposing
such a meter decrements the count instead of stopping it, so it leaves the registry
and keeps sampling.
- resolves each enforcer's meter once, where the enforcer is built, and holds it
- holds the timers alongside, though Timer is not reference counted, so a reader
is not left working out why one of two adjacent lookups was cached
- supplies the metrics in the session enforcer test, which builds the enforcer
directly to get a negative session timeout that NewSessionEnforcer refuses
Per enforcement cycle rather than per event, so the growth was one reference per
run. Unbounded over a controller's lifetime, but slow.
grep -rnE '\.(Meter|Histogram)\([^)]*\)\.(Mark|Update)' finds this shape; there are
no others left outside tests.
Paul Lorenz
49fdd2c0a1