1IFPPS(8) netsniff-ng toolkit IFPPS(8)
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6 ifpps - top-like networking and system statistics
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9 ifpps { [options] | [device] }
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12 ifpps is a small utility which periodically provides top-like network‐
13 ing and system statistics from the kernel. ifpps gathers its data
14 directly from procfs files and does not make use of any user space mon‐
15 itoring libraries which would falsify statistics under high load.
16 For instance, consider the following scenario: two directly connected
18 Linux machines with Intel Core 2 Quad Q6600 2.40GHz CPUs, 4 GB RAM, and
19 an Intel 82566DC-2 Gigabit Ethernet NIC are used for performance evalu‐
20 ation. One machine generates 64 byte network packets by using the ker‐
21 nel space packet generator pktgen with a maximum possible packet rate.
22 The other machine displays statistics about incoming network packets by
23 using i) iptraf(8) and ii) ifpps.
24 iptraf which incorporates pcap(3) shows an average packet rate of
26 246,000 pps while on the other hand ifpps shows an average packet rate
27 of 1,378,000 pps. Hence, due to packet copies and deferring statistics
28 creation into user space, a measurement error of approximately 460 per‐
29 cent occurs. Tools like iptraf might display much more information such
30 as TCP per flow statistics (hence the use of the pcap library). This is
31 not possible with ifpps, because overall networking statistics are its
32 focus; statistics, which are also fairly reliable under high packet
33 load.
34 ifpps also periodically displays CPU load, interrupt, software inter‐
36 rupt data per sample interval as well as total interrupts, all per CPU.
37 In case the number of CPUs exceeds 5 or the number specified by the
38 user with the “-n” command line option, ifpps will only display this
39 number top heavy hitters. The topmost heavy hitter CPU will be marked
40 with “+”. The least heavy hitter will always be displayed and is
41 marked with “-”. In addition, the average for all the above per-CPU
42 data is shown. Optionally the median values can be displayed using the
43 “-m” command line option.
44 ifpps also supports directly the gnuplot(1) data sample format. This
46 facilitates creation of gnuplot figures from ifpps time series.
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49 -d <netdev>, --dev <netdev>
50 Networking device to fetch statistics from, for example eth0, wlan0.
51 -n, --num-cpus
53 Set maximum number of top hitter CPUs (in terms of time spent in sys‐
54 tem/user mode) to display in ncurses mode, default is 10.
55 -t <time>, --interval <time>
57 Statistics refresh interval in milliseconds, default is 1000ms.
58 -c, --csv
60 Output (once) the ncurses data to the terminal as gnuplot(1)-ready
61 data.
62 -l, --loop
64 Continuously output the terminal data after a refresh interval. This
65 option is only available if option “-c” is given. For “-l” it is usu‐
66 ally recommended to redirect the output into a file that is to be pro‐
67 cessed later with gnuplot(1).
68 -m, --median
70 Show median values across all CPUs for CPU load, interrupts (per inter‐
71 val and absolute) and software interrupts.
72 -o, --omit-header
74 Omit printing the CSV header. This option is only available if “-c” is
75 given.
76 -p, --promisc
78 Turn on promiscuous mode for the given networking device.
79 -P, --percentage
81 Show percentage of current throughput in relation to theoretical line
82 rate.
83 -W, --no-warn
85 Suppress possible warnings in the ncurses output, e.g. about a too low
86 sampling interval that could cause performance regression.
87 -v, --version
89 Show version information.
90 -h, --help
92 Show user help.
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95 ifpps eth0
96 Default ncurses output for the eth0 device.
97 ifpps -pd eth0
99 Ncurses output for the eth0 device in promiscuous mode.
100 ifpps -lpcd wlan0 > plot.dat
102 Continuous terminal output for the wlan0 device in promiscuous mode.
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105 On 10Gbit/s cards or higher, receive and transmit statistics are usu‐
106 ally accumulated at a higher duration interval than 1 second. Thus, it
107 might be advisable to alter the timing to a higher accumulation inter‐
108 val for such cards.
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111 ifpps is licensed under the GNU GPL version 2.0.
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114 ifpps was originally written for the netsniff-ng toolkit by Daniel
115 Borkmann. It is currently maintained by Tobias Klauser <tklauser@dis‐
116 tanz.ch> and Daniel Borkmann <dborkma@tik.ee.ethz.ch>.
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119 netsniff-ng(8), trafgen(8), mausezahn(8), bpfc(8), flowtop(8),
120 astraceroute(8), curvetun(8)
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123 Manpage was written by Daniel Borkmann.
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126 This page is part of the Linux netsniff-ng toolkit project. A descrip‐
127 tion of the project, and information about reporting bugs, can be found
128 at http://netsniff-ng.org/.
129Linux 03 March 2013 IFPPS(8)