impstats: Generate Periodic Statistics of Internal Counters
===========================================================

This module provides periodic output of rsyslog internal counters.

The set of available counters will be output as a set of syslog
messages. This output is periodic, with the interval being configurable
(default is 5 minutes). Be sure that your configuration records the
counter messages (default is syslog.=info).

The impstats records are emitted just like regular log messages. As such,
counters increase when processing these messages. This must be taken into
consideration when testing and troubleshooting.

Note that loading this module has some impact on rsyslog performance.
Depending on settings, this impact may be noticable for high-load
environments, but in general the overhead is pretty light.

**Note that there is a** `rsyslog statistics online
analyzer <http://www.rsyslog.com/impstats-analyzer/>`_ **available.** It
can be given a impstats-generated file and will return problems it
detects. Note that the analyzer cannot replace a human in getting things
right, but it is expected to be a good aid in starting to understand and
gain information from the pstats logs.

The rsyslog website has an overview of available `rsyslog
statistic counters <http://rsyslog.com/rsyslog-statistic-counter/>`_. 
When browsing this page, please be sure to take note of which rsyslog
version is required to provide a specific counter. Counters are 
continously being added, and older versions do not support everything.

**Author:**\ Rainer Gerhards <rgerhards@adiscon.com>

Configuration Directives
------------------------

.. function:: $PStatInterval <Seconds>

   Sets the interval, in **seconds** at which messages are generated.
   Please note that the actual interval may be a bit longer. We do not
   try to be precise and so the interval is actually a sleep period
   which is entered after generating all messages. So the actual
   interval is what is configured here plus the actual time required to
   generate messages. In general, the difference should not really
   matter.

.. function:: $PStatFacility <numerical facility>

   The numerical syslog facility code to be used for generated
   messages. Default is 5 (syslog).This is useful for filtering
   messages.

.. function:: $PStatSeverity <numerical severity>

   The numerical syslog severity code to be used for generated
   messages. Default is 6 (info).This is useful for filtering messages.

Caveats/Known Bugs
------------------

-  This module MUST be loaded right at the top of rsyslog.conf,
   otherwise stats may not get turned on in all places.

Example
-------

This activates the module and records messages to /var/log/rsyslog-stats
in 10 minute intervals:

::

  $ModLoad impstats $PStatInterval 600 $PStatSeverity 7 syslog.debug /var/log/rsyslog-stats