news: add feature #4440

Signed-off-by: László Várady <[email protected]>

news/feature-4440.md

@@ -0,0 +1,10 @@
+`network()`, `syslog()`, `file()`, `http()`: new byte-based metrics for incoming/outgoing events
+
+These metrics are rounded to kibibytes and show the serialized message sizes
+(protocol-specific header/framing length is not included).
+
+```
+syslogng_input_event_bytes_total{id="s_network#0",driver_instance="tcp,127.0.0.1"} 1925529600
+syslogng_output_event_bytes_total{id="d_network#0",driver_instance="tcp,127.0.0.1:5555"} 565215232
+syslogng_output_event_bytes_total{id="d_http#0",driver_instance="http,http://127.0.0.1:8080/"} 1024
+```