+
−---
+
−labels:
+
−- 'Stage-Stable'
+
−summary: Log warning when event handlers take too long
+
−...
+
−
+
−Introduction
+
−============
+
−
+
−Most activities in Prosody take place within our built-in events framework, for
+
−example stanza processing and HTTP request handling, authentication, etc.
+
−
+
−Modules are able to execute code when an event occurs, and they should return
+
−as quickly as possible. Poor performance (e.g. slow or laggy server) can be caused
+
−by event handlers that are slow to respond.
+
−
+
−This module is able to monitor how long each event takes to be processed, and
+
−logs a warning if an event takes above a certain amount of time, including
+
−providing any details about the event such as the user or stanza that triggered it.
+
−
+
−The aim is to help debug why a server may not be as responsive as it should be,
+
−and ultimately which module is to blame for that.
+
−
+
−Configuration
+
−======================
+
−
+
−There is a single configuration option:
+
−
+
−```
+
−   -- Set the number of seconds an event may take before
+
−   -- logging a warning (fractional values are ok)
+
−   log_slow_events_threshold = 0.5
+
−```
+
−
+
−Metrics
+
−=======
+
−
+
−In addition to the log messages, a new 'slow_events' metric will be exported to
+
−your configured stats backend (if any).
+
−
+
−Compatibility
+
−-------------
+
−
+
−  ------- --------------
+
−  trunk   Works
+
−  0.10    Works
+
−  0.9     Doesn't work
+
−  0.8     Doesn't work
+
−  ------- --------------