NAME

       pmstat - high-level system performance overview

SYNOPSIS

       pmstat [-gLlPxz] [-A align] [-a archive] [-h host] [-H file] [-n pmnsfile] [-O offset] [-p
       port] [-S starttime] [-s samples] [-T endtime] [-t interval] [-Z timezone]

DESCRIPTION

       pmstat provides a one line summary of system performance every interval unit of time  (the
       default  is  5  seconds).  pmstat is intended to monitor system performance at the highest
       level, after which other tools may be  used  to  examine  subsystems  in  which  potential
       performance problems may be observed in greater detail.

       Multiple  hosts  may  be  monitored by supplying more than one host with multiple -h flags
       (for live monitoring) or by providing a name of the hostlist file, where each line contain
       one  host  name,  with  -H,  or  multiple  -a  flags (for retrospective monitoring from an
       archive).

       The -t option may be used to change the default reporting interval.  The interval argument
       follows  the  syntax described in PCPIntro(1), and in the simplest form may be an unsigned
       integer (the implied units in this case are seconds).

       By default, pmstat fetches metrics by connecting  to  the  Performance  Metrics  Collector
       Daemon (PMCD) on the local host.  If the -L option is specified, then pmcd(1) is bypassed,
       and metrics are fetched from PMDAs on the local host using the standalone PM_CONTEXT_LOCAL
       variant  of  pmNewContext(3).   When  the  -h  option is specified, pmstat connects to the
       pmcd(1) on host and fetches metrics from there.  As mentioned above, multiple hosts may be
       monitored by supplying multiple -h flags.

       Alternatively,  if  the  -a option is used, the metrics are retrieved from the Performance
       Co-Pilot archive log files identified by the base name archive.  Multiple archives may  be
       replayed  by  supplying multiple -a flags.  When the -a flag is used, the -P flag may also
       be used to pause the output after each interval.

       Standalone mode can only connect to the local host, using an archive implies a host  name,
       and  nominating  a  host  precludes  using  an  archive,  so the options -L, -a and -h are
       mutually exclusive.

       Normally pmstat operates on the default Performance Metrics Name Space (PMNS), however  if
       the -n option is specified an alternative namespace is loaded from the file pmnsfile.

       If  the  -s the option is specified, samples defines the number of samples to be retrieved
       and reported.  If samples is 0 or -s is not  specified,  pmstat  will  sample  and  report
       continuously - this is the default behavior.

       When processing an archive, pmstat may relinquish its own timing control, and operate as a
       ``slave'' of a pmtime(1) process that uses a GUI dialog to  provide  timing  control.   In
       this  case, either the -g option should be used to start pmstat as the sole slave of a new
       pmtime(1) instance, or -p should be  used  to  attach  pmstat  to  an  existing  pmtime(1)
       instance via the IPC channel identified by the port argument.

       The  -S, -T, -O and -A options may be used to define a time window to restrict the samples
       retrieved, set an initial  origin  within  the  time  window,  or  specify  a  ``natural''
       alignment  of  the  sample times; refer to PCPIntro(1) for a complete description of these
       options.

       The -l option prints the last 7 characters of a hostname in summaries involving more  than
       one host (when more than one -h option has been specified on the command line).

       The  -x  option  (extended  CPU metrics) causes two additional CPU metrics to be reported,
       namely wait for I/O ("wa") and virtualisation steal time ("st").

       The output from pmstat is directed to standard output, and the columns in the  report  are
       interpreted as follows:

       loadavg   The 1 minute load average.

       memory    The  swpd  column  indicates  average  swap  space  used during the interval, in
                 Kbytes.  The free column indicates average free memory during the  interval,  in
                 Kbytes.   The  buff  column  indicates  average  buffer memory in use during the
                 interval, in Kbytes.  The cache column indicates average cached  memory  in  use
                 during the interval, in Kbytes.

                 If  the values become large, they are reported as Mbytes (m suffix) or Gbytes (g
                 suffix).

       swap      The metrics in this area of the kernel instrumentation are of varying value.  We
                 try  to  report  the average number of pages that are paged in (pi) and out (po)
                 per second during the interval.  If the corresponding page swapping metrics  are
                 unavailable,  we  report  the average rate per second of swap operations in (si)
                 and out (so) during the interval.  It is normal for the ``in'' values to be non-
                 zero,  but  the system is suffering memory stress if the ``out'' values are non-
                 zero over an extended period.

                 If the values become large, they are reported as  thousands  of  operations  per
                 second (K suffix) or millions of operations per second (M suffix).

       io        The  bi  and  bo columns indicate the average rate per second of block input and
                 block output operations (respectfully) during the  interval.   Unless  all  file
                 systems  have  a 1 Kbyte block size, these rates do not directly indicate Kbytes
                 transferred.

                 If the values become large, they are reported as  thousands  of  operations  per
                 second (K suffix) or millions of operations per second (M suffix).

       system    Interrupt  rate  (in)  and  context  switch  rate  (cs).  Rates are expressed as
                 average operations per second during the interval.  Note that the interrupt rate
                 is  normally  at least HZ (the clock interrupt rate, usually 100) interrupts per
                 second.

                 If the values become large, they are reported as  thousands  of  operations  per
                 second (K suffix) or millions of operations per second (M suffix).

       cpu       Percentage  of  CPU  time spent executing user and "nice user" code (us), system
                 and interrupt processing code (sy), idle loop (id).

       If any values for the associated performance metrics are unavailable, the value appears as
       ``?'' in the output.

       By  default,  pmstat reports the time of day according to the local timezone on the system
       where pmstat is run.  The -Z option changes the timezone to timezone in the format of  the
       environment variable TZ as described in environ(7).  The -z option changes the timezone to
       the local timezone at the  host  that  is  the  source  of  the  performance  metrics,  as
       identified via either the -h or -a options.

FILES

       $PCP_VAR_DIR/pmns/*
                 default PMNS specification files
       $PCP_VAR_DIR/config/pmlogger/config.pmstat
                 pmlogger(1)  configuration  for  creating  an  archive  suitable for replay with
                 pmstat

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).

SEE ALSO

       PCPIntro(1),   pmclient(1),   pmtime(1),   PMAPI(3),   pmNewContext(3),   pcp.conf(5)  and
       pcp.env(5).

DIAGNOSTICS

       All are generated on standard error, and are intended to be self-explanatory.