CHANGELOG.md in statsd-instrument-3.3.0 vs CHANGELOG.md in statsd-instrument-3.4.0

- old
+ new

@@ -4,9 +4,15 @@
 creating a pull request, please add an entry to the "unreleased changes"
 section below.
 
 ### Unreleased changes
 
+- UDP Batching has been largely refactored again. The `STATSD_FLUSH_INTERVAL` environment variable
+  is deprecated. It still disable batching if set to `0`, but other than that is has no effect.
+  Setting `STATSD_BUFFER_CAPACITY` to `0` is now the recommended way to disable batching.
+- The synchronous UDP sink now use one socket per thread, instead of a single socket
+  protected by a mutex.
+
 ## Version 3.3.0
 
 - UDP Batching now has a max queue size and emitter threads will block if the queue
   reaches the limit. This is to prevent the queue from growing unbounded.
   More generally the UDP batching mode was optimized to improve throughput and to