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Revision: 1.1
Committed: Fri May 4 15:48:48 2007 UTC (17 years ago) by root
Branch: MAIN
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File Contents

# Content
1 NAME
2 Net::FPing - quickly ping a large number of hosts
3
4 SYNOPSIS
5 use Net::FPing;
6
7 DESCRIPTION
8 This module was written for a single purpose only: sendinf ICMP EHCO
9 REQUEST packets as quickly as possible to a large number of hosts
10 (thousands to millions).
11
12 It employs a sending thread and is fully event-driven (using AnyEvent),
13 so you have to run an event model supported by AnyEvent to use this
14 module.
15
16 FUNCTIONS
17 Net::FPing::ipv4_supported
18 Returns true if IPv4 is supported in this module and on this system.
19
20 Net::FPing::ipv6_supported
21 Returns true if IPv6 is supported in this module and on this system.
22
23 Net::FPing::icmp4_pktsize
24 Returns the number of bytes each IPv4 ping packet has.
25
26 Net::FPing::icmp6_pktsize
27 Returns the number of bytes each IPv4 ping packet has.
28
29 Net::FPing::icmp_ping [ranges...], $send_interval, $payload, \&callback
30 Ping the given IPv4 address ranges. Each range is an arrayref of the
31 form "[lo, hi, interval]", where "lo" and "hi" are octet strings
32 with either 4 octets (for IPv4 addresses) or 16 octets (for IPV6
33 addresses), representing the lowest and highest address to ping (you
34 can convert a dotted-quad IPv4 address to this format by using
35 "inet_aton $address". The range "interval" is the minimum time in
36 seconds between pings to the given range. If omitted, defaults to
37 $send_interval.
38
39 The $send_interval is the minimum interval between sending any two
40 packets and is a way to make an overall rate limit. If omitted,
41 pings will be send as fast as possible.
42
43 The $payload is a 32 bit unsigned integer given as the ICMP ECHO
44 REQUEST ident and sequence numbers (in unspecified order :).
45
46 The request will be queued and all requests will be served by a
47 background thread in order. When all ranges have been pinged, the
48 "callback" will be called.
49
50 Algorithm: Each range has an associated "next time to send packet"
51 time. The algorithm loops as long as there are ranges with hosts to
52 be pinged and always serves the range with the most urgent packet
53 send time. It will at most send one packet every $send_interval
54 seconds.
55
56 This will ensure that pings to the same range are nicely interleaved
57 with other ranges - this can help reduce per-subnet bandwidth while
58 maintaining an overall high packet rate.
59
60 The algorithm to send each packet is O(log n) on the number of
61 ranges, so even a large number of ranges (many thousands) is
62 managable.
63
64 No storage is allocated per address.
65
66 Performance: On my 2 GHz Opteron system with a pretty average nvidia
67 gigabit network card I can ping around 60k to 200k adresses per
68 second, depending on routing decisions.
69
70 Example: ping 10.0.0.1-10.0.0.15 with at most 100 packets/s, and
71 11.0.0.1-11.0.255.255 with at most 1000 packets/s. Do not, however,
72 exceed 1000 packets/s overall:
73
74 my $done = AnyEvent->condvar;
75
76 Net::FPing::icmp_ping
77 [v10.0.0.1, v10.0.0.15, .01],
78 [v11.0.0.1, v11.0.255.255, .001],
79 .001, 0x12345678,
80 sub {
81 warn "all ranges pinged\n";
82 $done->broadcast;
83 }
84 ;
85
86 $done->wait;
87
88 Net::FPing::register_cb \&cb
89 Register a callback that is called for every received ping reply
90 (regardless of whether a ping is still in process or not and
91 regardless of whether the reply is actually a reply ot a ping sent
92 earlier).
93
94 The code reference gets a single parameter - an arrayref with an
95 entry for each received packet (replies are beign batched for
96 greater efficiency). Each packet is represented by an arrayref with
97 three members: the source address (an octet string of either 4
98 (IPv4) or 16 (IPv6) octets length), the payload as passed to
99 "icmp_ping" and the round trip time in seconds.
100
101 Example: a single ping reply with payload of 1 from "::1" gets
102 passed like this:
103
104 [ [
105 "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\1",
106 "0.000280141830444336",
107 1
108 ] ]
109
110 Example: ping replies for 127.0.0.1 and 127.0.0.2, with a payload of
111 0x12345678:
112
113 [
114 [
115 "\177\0\0\1",
116 "0.00015711784362793",
117 305419896
118 ],
119 [
120 "\177\0\0\2",
121 "0.00090184211731",
122 305419896
123 ]
124 ]
125
126 Net::FPing::unregister_cb \&cb
127 Unregister the callback again (make sure you pass the same
128 codereference as to "register_cb").
129
130 AUTHOR
131 Marc Lehmann <schmorp@schmorp.de>
132 http://home.schmorp.de/
133
134 AUTHOR
135 This software is distributed under the GENERAL PUBLIC LICENSE,
136 version 2 or any later.
137