`ifpps` ( 8 )

топовая сетевая и системная статистика (top-like networking and system statistics)

Имя (Name)

ifpps - top-like networking and system statistics

Синопсис (Synopsis)

ifpps { [options] | [device] }

Описание (Description)

ifpps is a small utility which periodically provides top-like networking and system statistics from the kernel. ifpps gathers its data directly from procfs files and does not make use of any user space monitoring libraries which would falsify statistics under high load.

For instance, consider the following scenario: two directly connected Linux machines with Intel Core 2 Quad Q6600 2.40GHz CPUs, 4 GB RAM, and an Intel 82566DC-2 Gigabit Ethernet NIC are used for performance evaluation. One machine generates 64 byte network packets by using the kernel space packet generator pktgen with a maximum possible packet rate. The other machine displays statistics about incoming network packets by using i) iptraf(8) and ii) ifpps.

iptraf which incorporates pcap(3) shows an average packet rate of 246,000 pps while on the other hand ifpps shows an average packet rate of 1,378,000 pps. Hence, due to packet copies and deferring statistics creation into user space, a measurement error of approximately 460 percent occurs. Tools like iptraf might display much more information such as TCP per flow statistics (hence the use of the pcap library). This is not possible with ifpps, because overall networking statistics are its focus; statistics, which are also fairly reliable under high packet load.

ifpps also periodically displays CPU load, interrupt, software interrupt data per sample interval as well as total interrupts, all per CPU. In case the number of CPUs exceeds 5 or the number specified by the user with the -n command line option, ifpps will only display this number top heavy hitters. The topmost heavy hitter CPU will be marked with '+'. The least heavy hitter will always be displayed and is marked with '-'. In addition, the average for all the above per-CPU data is shown. Optionally the median values can be displayed using the -m command line option.

ifpps also supports directly the gnuplot(1) data sample format. This facilitates creation of gnuplot figures from ifpps time series.

Параметры (Options)

-d <netdev>, --dev <netdev>
              Networking device to fetch statistics from, for example
              eth0, wlan0.

       -n, --num-cpus
              Set maximum number of top hitter CPUs (in terms of time
              spent in system/user mode) to display in ncurses mode,
              default is 10.

       -t <time>, --interval <time>
              Statistics refresh interval in milliseconds, default is
              1000ms.

       -c, --csv
              Output (once) the ncurses data to the terminal as
              gnuplot(1)-ready data.

       -l, --loop
              Continuously output the terminal data after a refresh
              interval. This option is only available if option -c is
              given. For -l it is usually recommended to redirect the
              output into a file that is to be processed later with
              gnuplot(1).

       -m, --median
              Show median values across all CPUs for CPU load,
              interrupts (per interval and absolute) and software
              interrupts.

       -o, --omit-header
              Omit printing the CSV header. This option is only
              available if -c is given.

       -p, --promisc
              Turn on promiscuous mode for the given networking device.

       -P, --percentage
              Show percentage of current throughput in relation to
              theoretical line rate.

       -W, --no-warn
              Suppress possible warnings in the ncurses output, e.g.
              about a too low sampling interval that could cause
              performance regression.

       -v, --version
              Show version information.

       -h, --help
              Show user help.

Примеры использования (Usage example)

ifpps eth0
              Default ncurses output for the eth0 device.

       ifpps -pd eth0
              Ncurses output for the eth0 device in promiscuous mode.

       ifpps -lpcd wlan0 > plot.dat
              Continuous terminal output for the wlan0 device in
              promiscuous mode.

Примечание (Note)

On 10Gbit/s cards or higher, receive and transmit statistics are usually accumulated at a higher duration interval than 1 second. Thus, it might be advisable to alter the timing to a higher accumulation interval for such cards.

История (History)

ifpps was originally written for the netsniff-ng toolkit by Daniel Borkmann. It is currently maintained by Tobias Klauser <tklauser@distanz.ch> and Daniel Borkmann <dborkma@tik.ee.ethz.ch>.

Смотри также (See also)

netsniff-ng(8), trafgen(8), mausezahn(8), bpfc(8), flowtop(8), astraceroute(8), curvetun(8)

Исходный текст на man7.org

ifpps ( 8 )