IFPPS(8)							netsniff-ng toolkit							  IFPPS(8)

NAME

       ifpps - top-like networking and system statistics

SYNOPSIS

       ifpps { [options] | [device] }

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 per-
       cent  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.

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 usu-
       ally recommended to redirect the output into a file that is to be 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.

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

   -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.

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.

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.

LEGAL

       ifpps is licensed under the GNU GPL version 2.0.

HISTORY

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

SEE ALSO

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

AUTHOR

       Manpage was written by Daniel Borkmann.

COLOPHON

       This page is part of the Linux netsniff-ng toolkit project. A description of the project, and information  about  reporting  bugs,  can	be
       found at http://netsniff-ng.org/.

Linux								   03 March 2013							  IFPPS(8)