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
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
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 somehostss -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 16Jun 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 pmdumplog -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 curently growing
(i.e. being logged with pmlogger(1)).
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:
The remote hostname to connect to in live mode.
The archive file to use for historical sampling
The time offset to use within an archive (implies -a)
The start time (e.g. in ctime(3) format) to use when
replaying an archive.
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).
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 pmdumplog(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
show help message and exit
output version information
don't resolve service names
resolve host names
display all sockets
display listening sockets
show timer information
show detailed socket information
show socket memory usage
show process using socket
show internal TCP information
show socket usage summary
show bpf filter socket information
continually display sockets as they are destroyed
display process SELinux security contexts
display process and socket SELinux security contexts
switch to the specified network namespace name
display only IP version 4 sockets
display only IP version 6 sockets
display PACKET sockets
display only TCP sockets
display only MPTCP sockets
display only SCTP sockets
display only UDP sockets
display only DCCP sockets
display only RAW sockets
display only Unix domain sockets
Suppress header line
socket's data printed on a single line
The columns in the pcp-ss report vary according to the command
line options and have the same interpretation as described in
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. pmstorenetwork.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.
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
For environment variables affecting PCP tools, see
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 firstname.lastname@example.org. This page was obtained from the
project's upstream Git repository
⟨https://github.com/performancecopilot/pcp.git⟩ on 2023-06-23.
(At that time, the date of the most recent commit that was found
in the repository was 2023-06-21.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
Performance Co-Pilot PCP PCP-SS(1)