Ring
Keeps the last capacity events, for tests, crash reports and ad-hoc export.
Lock-free and safe for concurrent emit from many threads. Implementation: a sequence counter claims a slot (seq % capacity) among capacity AtomicReferences (the common stdlib has no atomic array primitive); the slot holds an immutable (seq, event) pair and is replaced by compare-and-set only when the stored sequence is older, so a delayed writer can never overwrite a newer event. snapshot reads the slots and orders by sequence. This avoids copying the whole buffer on every emit (which a CAS loop over one immutable snapshot would do). An event whose slot is claimed but not yet written may be briefly absent from a concurrent snapshot, which is acceptable for a diagnostic sink.
Example:
val ring = RingBufferSink(capacity = 256)
// ... run traced work ...
ring.snapshot().forEach(::println)Once more than capacity events were emitted, the oldest ones are overwritten.
Requires opting in to ExperimentalStructuredCoroutines.
Parameters
maximum number of retained events; must be positive.
highest TraceLevel this sink accepts.
See also
Throws
if capacity is not positive.
Properties
Functions
Receives one event. See the contract in the type documentation.
Whether this sink wants events of level. Defaults to true for every level.
Returns a copy of the retained events, oldest first (at most capacity elements). The list is not updated by later events.