pcp-ss(1) — Linux manual page
PCP-SS(1) General Commands Manual PCP-SS(1)
NAME
pcp-ss - report socket statistics
SYNOPSIS
pcp [pcp options] ss [ss options]
DESCRIPTION
pcp-ss reports socket statistics collected by the pmdasockets(1)
PMDA agent. The command is intended to be reasonably compatible
with many of the ss(8) command line options and reporting
formats, but also offer the advantages of local or remote
monitoring (in live mode) and also historical replay from a
previously recorded PCP archive. Note that since ss(1) has many
command line options, many of which are the same as standard PCP
command line options as described in PCPIntro(1), the pcp-ss tool
should always be invoked by users using the pcp front-end. This
allows standard PCP commandline options such as -h, -a, -S, -T,
-O, -z, etc to be passed without conflict with ss(1) options.
See the EXAMPLES sections below for typical usage and command
lines.
Live mode uses the pcp -h host option and requires the
pmdasockets(1) PMDA to be installed and enabled on the target
host (local or remote), see pmdasockets(1) for details on how to
enable the sockets PMDA on a particular host. The default source
is live metrics collected on localhost, if neither of the -h or
-a options are given.
Historical/archive replay uses the pcp -a archive option, where
archive is the basename of a previously recorded PCP archive.
The archive replay feature is particularly useful because socket
statistics can be reported for a designated time using the pcp
--origin option (which defaults to the start time of the
archive).
EXAMPLES
pcp ss
Display default basic socket information for the local host.
This includes Netid (tcp, udp, etc), State (ESTAB,
TIME_WAIT, etc), Recv-Q and Send-Q queue lengths and the
local and peer address and port for each socket.
pcp -h somehost ss -noemitauO
Display the same basic socket information as above for the
host somehost, which may be the default localhost. The
additional command line arguments (-noemitauO) display one
line per socket (-O), numeric (-n) service names (default),
timer information (-o), extended socket details (-e), socket
memory usage (-m), internal TCP information (-i), both udp
(-u) and tcp sockets (-t) and both listening and non-
listening sockets (-a).
pcp -a somearchive -S'@Wed 16 Jun 2021 12:57:21' ss -noemitauO
Display the same information as the above example, but for
the archive somearchive starting at the given time Wed 16
Jun 2021 12:57:21. Note the literal @ prefix is required
for an absolute time, see PCPIntro(1) for details. The
archive must of course contain data for the requested time.
You can use pmlogdump -l somearchive to examine the time
bounds of somearchive.
pcp -a somearchive -O-0 ss -noemitauO
As above, but with an offset of zero seconds (-O-0) before
the current end of somearchive, i.e. the most recently
logged data. Note that somearchive may be currently growing
(i.e. being logged with pmlogger(1)).
OPTIONS
Due to the large number of options supported by pcp-ss, the
pcp(1) command should always be used to invoke pcp-ss in order to
specify options such as the metrics source (host or archive) and
also (in archive mode), the requested start time or offset, and
timezone using the following options:
-h, --host
The remote hostname to connect to in live mode.
-a, --archive
The archive file to use for historical sampling
-O, --origin
The time offset to use within an archive (implies -a)
-S, --start
The start time (e.g. in ctime(3) format) to use when
replaying an archive.
-Z, --timezone
Use a specific timezone. Since pcp-ss doesn't report
timestamps, this only affects the interpretation of an
absolute starting time (-S) or offset (-O).
-z, --hostzone
In archive mode, use the timezone of the archive rather than
the timezone on the local machine running pcp-ss. The
timezone, start and finish times of the archive may be
examined using pmlogdump(1) with the -L option.
The above pcp options become indirectly available to the pcp-ss
command via environment variables - refer to PCPIntro(1) for a
complete description of these options.
The additional command line options available for pcp-ss itself
are:
-h, --help
show help message and exit
-V, --version
output version information
-n, --numeric
don't resolve service names (currently always set)
-a, --all
display all sockets
-l, --listening
display listening sockets
-o, --options
show timer information
-e, --extended
show detailed socket information
-m, --memory
show socket memory usage
-i, --info
show internal TCP information
-4, --ipv4
display only IP version 4 sockets
-6, --ipv6
display only IP version 6 sockets
-t, --tcp
display only TCP sockets
-u, --udp
display only UDP sockets
-H, --noheader
Suppress header line
-O, --oneline
socket's data printed on a single line
REPORT
The columns in the pcp-ss report vary according to the command
line options and have the same interpretation as described in
ss(8).
One difference with pcp-ss is that the first line in the report
begins with '# Timestamp' followed by the timestamp (in the
requested timezone, see -z and -Z above) of the sample data from
the host or archive source. Following the timestamp is the
currently active filter string for the metrics source. In
archive mode, the active filter can be changed dynamically, even
whilst the archive is being recorded. This is different to ss(8)
where the filter is optionally specified on the command line of
the tool and is always 'live', i.e. ss(8) does not support
retrospective replay. With pcp-ss, the filter is stored in the
back-end PMDA, see pmdasockets(1), in the metric
network.persocket.filter. The default filter is state connected,
which can be changed by storing a new string value in the
network.persocket.filter metric using pmstore(1), e.g. pmstore
network.persocket.filter "state established". This will override
the persistent default filter, which is stored in a PMDA
configuration file and loaded each time the sockets PMDA is
started. See pmdasockets(1) for further details and see ss(8)
for details of the filter syntax and examples.
PCP ENVIRONMENT
Environment variables with the prefix PCP_ are used to
parameterize the file and directory names used by PCP. On each
installation, the file /etc/pcp.conf contains the local values
for these variables. The $PCP_CONF variable may be used to
specify an alternative configuration file, as described in
pcp.conf(5).
For environment variables affecting PCP tools, see
pmGetOptions(3).
SEE ALSO
PCPIntro(1), pcp(1), pmdasockets(1), pmlogger(1), pcp.conf(5) and
ss(8).
COLOPHON
This page is part of the PCP (Performance Co-Pilot) project.
Information about the project can be found at
⟨http://www.pcp.io/⟩. If you have a bug report for this manual
page, send it to pcp@groups.io. This page was obtained from the
project's upstream Git repository
⟨https://github.com/performancecopilot/pcp.git⟩ on 2024-06-14.
(At that time, the date of the most recent commit that was found
in the repository was 2024-06-14.) If you discover any rendering
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is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
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