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)
