Adaptive Flushing

This extension uses an adaptive flushing model, similar to the one implemented in Datadog's new Rust Lambda extension.

On the initial invocation after a cold start, the extension flushes all telemetry data at the end of each function invocation. This ensures minimal delay in telemetry availability. However, because the flush happens after the invocation completes, it can slightly increase the billed duration of the function.

If the extension detects a regular invocation pattern—such as invocations occurring at least once per minute—it will switch to periodic flushing at the start of each invocation. This overlaps the flush operation with the function’s execution time, reducing the likelihood of added billed duration due to telemetry flushing.

For long-running invocations, a global backup timer is used to flush telemetry periodically. This timer is reset whenever a regular flush occurs, ensuring that telemetry is still sent even if invocation patterns become irregular.