1Net::Statsd(3)        User Contributed Perl Documentation       Net::Statsd(3)
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NAME

6       Net::Statsd - Perl client for Etsy's statsd daemon
7

VERSION

9       version 0.12
10

SYNOPSIS

12           # Configure where to send events
13           # That's where your statsd daemon is listening.
14           $Net::Statsd::HOST = 'localhost';    # Default
15           $Net::Statsd::PORT = 8125;           # Default
16
17           #
18           # Keep track of events as counters
19           #
20           Net::Statsd::increment('site.logins');
21           Net::Statsd::increment('database.connects');
22
23           #
24           # Log timing of events, ex. db queries
25           #
26           use Time::HiRes;
27           my $start_time = [ Time::HiRes::gettimeofday ];
28
29           # do the complex database query
30           # note: time value sent to timing should
31           # be in milliseconds.
32           Net::Statsd::timing(
33               'database.complexquery',
34               Time::HiRes::tv_interval($start_time) * 1000
35           );
36
37           #
38           # Log metric values
39           #
40           Net::Statsd::gauge('core.temperature' => 55);
41

DESCRIPTION

43       This module implement a UDP client for the statsd statistics collector
44       daemon in use at Etsy.com.
45
46       You want to use this module to track statistics in your Perl
47       application, such as how many times a certain event occurs (user logins
48       in a web application, or database queries issued), or you want to time
49       and then graph how long certain events take, like database queries
50       execution time or time to download a certain file, etc...
51
52       If you're uncertain whether you'd want to use this module or statsd,
53       then you can read some background information here:
54
55           http://codeascraft.etsy.com/2011/02/15/measure-anything-measure-everything/
56
57       The github repository for statsd is:
58
59           http://github.com/etsy/statsd
60
61       By default the client will try to send statistic metrics to
62       "localhost:8125", but you can change the default hostname and port
63       with:
64
65           $Net::Statsd::HOST = 'your.statsd.hostname.net';
66           $Net::Statsd::PORT = 9999;
67
68       just after including the "Net::Statsd" module.
69

ABOUT SAMPLING

71       A note about sample rate: A sample rate of < 1 instructs this library
72       to send only the specified percentage of the samples to the server. As
73       such, the application code should call this module for every occurence
74       of each metric and allow this library to determine which specific
75       measurements to deliver, based on the sample_rate value. (e.g. a sample
76       rate of 0.5 would indicate that approximately only half of the metrics
77       given to this module would actually be sent to statsd).
78

FUNCTIONS

80   "timing($name, $time, $sample_rate = 1)"
81       Log timing information.  Time is assumed to be in milliseconds (ms).
82
83           Net::Statsd::timing('some.timer', 500);
84
85   "increment($counter, $sample_rate=1)"
86   "increment(\@counter, $sample_rate=1)"
87       Increments one or more stats counters
88
89           # +1 on 'some.int'
90           Net::Statsd::increment('some.int');
91
92           # 0.5 = 50% sampling
93           Net::Statsd::increment('some.int', 0.5);
94
95       To increment more than one counter at a time, you can pass an array
96       reference:
97
98           Net::Statsd::increment(['grue.dinners', 'room.lamps'], 1);
99
100       You can also use "inc()" instead of "increment()" to type less.
101
102   "decrement($counter, $sample_rate=1)"
103       Same as increment, but decrements. Yay.
104
105           Net::Statsd::decrement('some.int')
106
107       You can also use "dec()" instead of "decrement()" to type less.
108
109   "update_stats($stats, $delta=1, $sample_rate=1)"
110       Updates one or more stats counters by arbitrary amounts
111
112           Net::Statsd::update_stats('some.int', 10)
113
114       equivalent to:
115
116           Net::Statsd::update_stats('some.int', 10, 1)
117
118       A sampling rate less than 1 means only update the stats every x number
119       of times (0.1 = 10% of the times).
120
121   "gauge($name, $value)"
122       Log arbitrary values, as a temperature, or server load.
123
124           Net::Statsd::gauge('core.temperature', 55);
125
126       Statsd interprets gauge values with "+" or "-" sign as
127       increment/decrement.  Therefore, to explicitly set a gauge to a
128       negative number it has to be set to zero first.
129
130       However, if either the zero or the actual negative value is lost in UDP
131       transport to statsd server because of e.g. network congestion or packet
132       loss, your gauge will become skewed.
133
134       To ensure network problems will not skew your data,
135       "Net::Statsd::gauge()" supports packing multiple values in single UDP
136       packet sent to statsd:
137
138           Net::Statsd::gauge(
139               'core.temperature' => 55,
140               'freezer.temperature' => -18
141           );
142
143       Make sure you don't supply too many values, or you might risk exceeding
144       the MTU of the network interface and cause the resulting UDP packet to
145       be dropped.
146
147       In general, a safe limit should be 512 bytes. Related to the example
148       above, "core.temperature" of 55 will be likely packed as a string:
149
150           core.temperature:55|g
151
152       which is 21 characters, plus a newline used as delimiter (22).  Using
153       this example, you can pack at least 20 distinct gauge values without
154       problems. That will result in a UDP message of 440 bytes (22 times 20),
155       which is well below the safe threshold of 512.
156
157       In reality, if the communication happens on a local interface, or over
158       a 10G link, you are allowed much more than that.
159
160   "send(\%data, $sample_rate = 1)"
161       Squirt the metrics over UDP.
162
163           Net::Statsd::send({ 'some.int' => 1 });
164
165   "_sample_data(\%data, $sample_rate = 1)"
166       This method is used internally, it's not part of the public interface.
167
168       Takes care of transforming a hash of metrics data into a sampled hash
169       of metrics data, according to the given $sample_rate.
170
171       If "$sample_rate == 1", then sampled data is exactly the incoming data.
172
173       If "$sample_rate = 0.2", then every metric value will be marked with
174       the given sample rate, so the Statsd server will automatically scale
175       it. For example, with a sample rate of 0.2, the metric values will be
176       multiplied by 5.
177

AUTHOR

179       Cosimo Streppone <cosimo@cpan.org>
180
182       This software is copyright (c) 2016 by Cosimo Streppone.
183
184       This is free software; you can redistribute it and/or modify it under
185       the same terms as the Perl 5 programming language system itself.
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189perl v5.32.1                      2021-01-27                    Net::Statsd(3)
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