news: add entry for #4402

Signed-off-by: Attila Szakacs <attila.szakacs@axoflow.com>

Author: alltilla

news/feature-4402.md

@@ -0,0 +1,11 @@
+`disk-buffer`: Added metrics for abandoned disk-buffer files.
+
+Availability is the same as the `disk_queue_dir_available_bytes` metric.
+
+Example metrics:
+```
+syslogng_disk_queue_capacity_bytes{abandoned="true",path="/var/syslog-ng/syslog-ng-00000.rqf",reliable="true"} 104853504
+syslogng_disk_queue_disk_allocated_bytes{abandoned="true",path="/var/syslog-ng/syslog-ng-00000.rqf",reliable="true"} 273408
+syslogng_disk_queue_disk_usage_bytes{abandoned="true",path="/var/syslog-ng/syslog-ng-00000.rqf",reliable="true"} 269312
+syslogng_disk_queue_events{abandoned="true",path="/var/syslog-ng/syslog-ng-00000.rqf",reliable="true"} 860
+```