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Tail::Stat(3)	      User Contributed Perl Documentation	 Tail::Stat(3)

       Tail::Stat - Real-time log statistics server

       It's often necessary to collect some statistics data for	following
       analysis	or processing. Common case are various monitoring tools, like
       a MRTG, Nagios or Zabbix. Some services may be examined by special
       commands	or protocols, other may	not. But often,	information we are
       interested in can be extracted from server logs.	This software helps to
       extract,	accumulate and provide this information	to monitoring tool via
       simple, easy parseable protocol.

       Tail::Stat has a	plugin structure. Each plugin supports logs processing
       for a specific service. Main executable (called tstatd) works as	a long
       running background process (daemon) with	TCP listen socket for querying
       about collected statistics. There is no any configuration files,	all
       required	parameters tstatd takes	from command line options.  One
       running instance	of tstatd can process many similar log files
       simultaneously. It agregates extracted parameters into zones.  Zones
       are just	namespaces for grouping	this values.  For collecting
       parameters from other kind of service you have to run other instance of

       Fundamentally all measured values can be	separated into two principally
       different groups: counters and gauges.  For example, processing web-
       server logs we want to calculate	two parameters:	total processed	HTTP
       requests	and average time elapsed per request.  The first goal can be
       achieved	by simple incremented counter, but the second is a little
       harder. We have to summarize elapsed times and then divide this amount
       onto request count. But we have to do this for a	small time slot
       (usually	comparable with	our monitoring tool polling interval).	This
       kind of calculations is supported by Tail::Stat and calls sliding
       windows calculations. Tail::Stat	operate	with a set of a	small windows.
       First window (called current) accumulates current data.	After a	fixed
       period of time ("--window-size")	a window is closing (special handler
       executing), new window creating and setting as current and last of
       closed windows is removing. Total number	of windows can be adjusted by
       special option ("--windows-num"). For example: our monitoring tool has
       a polling interval about	10 minutes (600	seconds). We want to provide
       it average response time	for last 600 seconds respectively. Appropriate
       window size can be set as 10 seconds with keeping values	for 60 windows
       (and this are default values).

       Querying	accumulated data is available via simple TCP-based protocol.
       Protocol	is line	oriented (like an HTTP or SMTP).

       Prints list of known zones. Zones specified via command line options
       marked with 'a:'	prefix (active). Zones restored	from a database	file,
       but not found in	command	options	marked with 'i:' prefix	(inactive).

   globs zone
       Prints list of globs (wildcards)	associated with	zone. Applicable only
       to active zones.

   files zone
       Prints list of files currently processing for zone. Each	file prefixed
       by current reading offset and size of file. Applicable only to active

   wipe	zone|*
       Wipes out an inactive zone or all inactive zones. Applicable only to
       inactive	zones.

   dump	zone
       Prints out raw zone statistics.

   stats zone
       Prints out formatted zone statistics.

       Closes client connection.

       Please report any bugs or feature requests to "bug-tail-stat at", or	through	the web	interface at
       <>.  I will be
       notified, and then you'll automatically be notified of progress on your
       bug as I	make changes.

       You can find documentation for this module with the perldoc command.

	   perldoc Tail::Stat

       You can also look for information at:

       o   RT: CPAN's request tracker


       o   AnnoCPAN: Annotated CPAN documentation


       o   CPAN	Ratings


       o   Search CPAN


       Oleg A. Mamontov, "<>"

       This program is free software; you can redistribute it and/or modify it
       under the terms of either: the GNU General Public License as published
       by the Free Software Foundation;	or the Artistic	License.

       See for more information.

perl v5.32.0			  2016-12-03			 Tail::Stat(3)


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