Provided by: pcp_4.0.1-1_amd64 bug

NAME

       pmie - inference engine for performance metrics

SYNOPSIS

       pmie  [-bCdefHqVvWxz]  [-A  align]  [-a  archive] [-c filename] [-h host] [-l logfile] [-j
       stompfile] [-n pmnsfile] [-O  offset]  [-S  starttime]  [-T  endtime]  [-t  interval]  [-U
       username] [-Z timezone] [filename ...]

DESCRIPTION

       pmie  accepts a collection of arithmetic, logical, and rule expressions to be evaluated at
       specified frequencies.  The base data for the expressions consists of performance  metrics
       values  delivered  in  real-time  from any host running the Performance Metrics Collection
       Daemon (PMCD), or using historical data from Performance Co-Pilot (PCP) archive logs.

       As well as computing arithmetic and  logical  values,  pmie  can  execute  actions  (popup
       alarms,  write  system  log  messages,  and  launch  programs)  in  response  to specified
       conditions.  Such actions are extremely useful in  detecting,  monitoring  and  correcting
       performance related problems.

       The expressions to be evaluated are read from configuration files specified by one or more
       filename arguments.  In the absence of any filename, expressions are  read  from  standard
       input.

       A description of the command line options specific to pmie follows:

       -a   archive  which is a comma-separated list of names, each of which may be the base name
            of an archive or the name of a directory containing one or more archives  written  by
            pmlogger(1).   Multiple  instances  of  the -a flag may appear on the command line to
            specify a list of sets of archives.  In this case, it is required that only  one  set
            of  archives be present for any one host.  Also, any explicit host names occurring in
            a pmie expression must match the host name recorded in one of the archive labels.  In
            the  case  of multiple sets of archives, timestamps recorded in the archives are used
            to ensure temporal consistency.

       -b   Output will be line buffered and standard output is attached to standard error.  This
            is  most  useful  for background execution in conjunction with the -l option.  The -b
            option is always used for pmie instances launched from pmie_check(1).

       -C   Parse the configuration file(s) and exit  before  performing  any  evaluations.   Any
            errors in the configuration file are reported.

       -c   An alternative to specifying filename at the end of the command line.

       -d   Normally  pmie  would  be launched as a non-interactive process to monitor and manage
            the performance of one or more hosts.   Given  the  -d  flag  however,  execution  is
            interactive  and  the  user is presented with a menu of options.  Interactive mode is
            useful mainly for debugging new expressions.

       -e   When used with -V, -v or -W, this option forces timestamps to be reported  with  each
            expression.   The  timestamps  are  in  ctime(3)  format, enclosed in parenthesis and
            appear after the expression name and before the expression value, e.g.
                 expr_1 (Tue Feb  6 19:55:10 2001): 12

       -f   If the -l option is specified and there is no -a option  (ie.  real-time  monitoring)
            then  pmie is run as a daemon in the background (in all other cases foreground is the
            default).  The -f option forces pmie to be run in the foreground, independent of  any
            other options.

       -h   By default performance data is fetched from the local host (in real-time mode) or the
            host for the first named set of archives on the command line (in archive mode).   The
            host argument overrides this default.  It does not override hosts explicitly named in
            the expressions being evaluated.  The host argument is interpreted  as  a  connection
            specification  for  pmNewContext,  and  is  later  mapped  to the remote pmcd's self-
            reported host name for reporting purposes.  See also the %h vs. %c  substitutions  in
            rule action strings below.

       -l   Standard error is sent to logfile.

       -j   An alternative STOMP protocol configuration is loaded from stompfile.  If this option
            is not used, and the  stomp  action  is  used  in  any  rule,  the  default  location
            $PCP_SYSCONF_DIR/pmie/config/stomp will be used.

       -n   An  alternative  Performance  Metrics  Name  Space  (PMNS)  is  loaded  from the file
            pmnsfile.

       -q   Suppresses diagnostic messages that would be printed to standard output  by  default,
            especially the "evaluator exiting" message as this can confuse scripts.

       -t   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).  The value is used to determine the sample interval for expressions that do
            not explicitly set their sample interval using  the  pmie  variable  delta  described
            below.  The default is 10.0 seconds.

       -U username
            User  account  under  which to run pmie.  The default is the current user account for
            interactive use.  When run as a daemon, the unprivileged "pcp"  account  is  used  in
            current  versions  of  PCP,  but in older versions the superuser account ("root") was
            used by default.

       -v   Unless one of the verbose  options  -V,  -v  or  -W  appears  on  the  command  line,
            expressions  are  evaluated  silently,  the only output is as a result of any actions
            being executed.  In the verbose mode, specified using the -v flag, the value of  each
            expression  is  printed as it is evaluated.  The values are in canonical units; bytes
            in the dimension of ``space'', seconds in the dimension of ``time'' and events in the
            dimension  of  ``count''.  See pmLookupDesc(3) for details of the supported dimension
            and scaling mechanisms for performance  metrics.   The  verbose  mode  is  useful  in
            monitoring  the  value  of given expressions, evaluating derived performance metrics,
            passing these values on to other tools for further processing and  in  debugging  new
            expressions.

       -V   This  option  has  the same effect as the -v option, except that the name of the host
            and instance (if applicable) are printed as well as expression values.

       -W   This option has the same effect as the -V option described  above,  except  that  for
            boolean  expressions,  only  those names and values that make the expression true are
            printed.  These are the same names and values accessible to rule actions as  the  %h,
            %i, %c and %v bindings, as described below.

       -x   Execute  in  domain  agent  mode.   This mode is used within the Performance Co-Pilot
            product to derive values for summary metrics, see  pmdasummary(1).   Only  restricted
            functionality is available in this mode (expressions with actions may not be used).

       -Z   Change  the  reporting timezone to timezone in the format of the environment variable
            TZ as described in environ(7).

       -z   Change the reporting timezone to the timezone of the host that is the source  of  the
            performance metrics, as identified via either the -h option or the first named set of
            archives (as described above for the -a option).

       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.

       Output from pmie is directed to standard output and standard error as follows:

       stdout
            Expression values printed in the verbose -v mode and the output of print actions.

       stderr
            Error  and  warning messages for any syntactic or semantic problems during expression
            parsing, and  any  semantic  or  performance  metrics  availability  problems  during
            expression evaluation.

EXAMPLES

       The  following  example  expressions demonstrate some of the capabilities of the inference
       engine.

       The directory $PCP_DEMOS_DIR/pmie contains a number of other annotated  examples  of  pmie
       expressions.

       The  variable  delta  controls  expression  evaluation frequency.  Specify that subsequent
       expressions be evaluated once a second, until further notice:

            delta = 1 sec;

       If the total context switch rate exceeds 10000 per second per CPU, then display  an  alarm
       notifier:

            kernel.all.pswitch / hinv.ncpu > 10000 count/sec
            -> alarm "high context switch rate %v";

       If  the  high  context  switch  rate  is sustained for 10 consecutive samples, then launch
       top(1) in an xterm(1) window to monitor processes, but  do  this  at  most  once  every  5
       minutes:

            all_sample (
                kernel.all.pswitch @0..9 > 10 Kcount/sec * hinv.ncpu
            ) -> shell 5 min "xterm -e 'top'";

       The following rules are evaluated once every 20 seconds:

            delta = 20 sec;

       If  any  disk is performing more than 60 I/Os per second, then print a message identifying
       the busy disk to standard output and launch dkvis(1):

            some_inst (
                disk.dev.total > 60 count/sec
            ) -> print "busy disks:" " %i" &
                 shell 5 min "dkvis";

       Refine the preceding rule to apply only between the hours of 9am and 5pm, and to require 3
       of 4 consecutive samples to exceed the threshold before executing the action:

            $hour >= 9 && $hour <= 17 &&
            some_inst (
              75 %_sample (
                disk.dev.total @0..3 > 60 count/sec
              )
            ) -> print "disks busy for 20 sec:" " [%h]%i";

       The following two rules are evaluated once every 10 minutes:

            delta = 10 min;

       If  either the / or the /usr filesystem is more than 95% full, display an alarm popup, but
       not if it has already been displayed during the last 4 hours:

            filesys.free #'/dev/root' /
                filesys.capacity #'/dev/root' < 0.05
            -> alarm 4 hour "root filesystem (almost) full";

            filesys.free #'/dev/usr' /
                filesys.capacity #'/dev/usr' < 0.05
            -> alarm 4 hour "/usr filesystem (almost) full";

       The following rule requires a machine that supports the PCP environment metrics.   If  the
       machine environment temperature rises more than 2 degrees over a 10 minute interval, write
       an entry in the system log:

            environ.temp @0 - environ.temp @1 > 2
            -> alarm "temperature rising fast" &
               syslog "machine room temperature rise alarm";

       And something interesting if you have performance problems with your Oracle database:

            // back to 30sec evaluations
            delta = 30 sec;
            sid = "ptg1";       # $ORACLE_SID setting
            lid = "223";        # latch ID from v$latch
            lru = "#'$sid/$lid cache buffers lru chain'";
            host = ":moomba.melbourne.sgi.com";
            gets = "oracle.latch.gets $host $lru";
            total = "oracle.latch.gets $host $lru +
                     oracle.latch.misses $host $lru +
                     oracle.latch.immisses $host $lru";

            $total > 100 && $gets / $total < 0.2
            -> alarm "high lru latch contention in database $sid";

       The following ruleset will emit exactly one message  depending  on  the  availability  and
       value of the 1-minute load average.

            delta = 1 minute;
            ruleset
                 kernel.all.load #'1 minute' > 10 * hinv.ncpu ->
                     print "extreme load average %v"
            else kernel.all.load #'1 minute' > 2 * hinv.ncpu ->
                     print "moderate load average %v"
            unknown ->
                     print "load average unavailable"
            otherwise ->
                     print "load average OK"
            ;

       The  following  rule will emit a message when some filesystem is more than 75% full and is
       filling at a rate that if sustained would fill the filesystem to  100%  in  less  than  30
       minutes.

            some_inst (
                100 * filesys.used / filesys.capacity > 75 &&
                filesys.used + 30min * (rate filesys.used) > filesys.capacity
            ) -> print "filesystem will be full within 30 mins:" " %i";

       If  the  metric mypmda.errors counts errors then the following rule will emit a message if
       the rate of errors exceeds 1 per second provided the error count is less than 100.

            mypmda.errors > 1 && instant mypmda.errors < 100
            -> print "high error rate: %v";

QUICK START

       The pmie specification language is powerful and large.

       To expedite rapid development of pmie rules, the pmieconf(1) tool provides a facility  for
       generating  a  pmie configuration file from a set of generalized pmie rules.  The supplied
       set of rules covers a wide range of performance scenarios.

       The Performance Co-Pilot User's and Administrator's Guide provides  a  detailed  tutorial-
       style chapter covering pmie.

EXPRESSION SYNTAX

       This  description  is  terse  and  informal.  For a more comprehensive description see the
       Performance Co-Pilot User's and Administrator's Guide.

       A pmie specification is a sequence of semicolon terminated expressions.

       Basic operators are modeled on the arithmetic, relational and Boolean operators of  the  C
       programming  language.   Precedence rules are as expected, although the use of parentheses
       is encouraged to enhance readability and remove ambiguity.

       Operands are performance metric names (see pmns(5)) and the normal literal constants.

       Operands involving performance metrics  may  produce  sets  of  values,  as  a  result  of
       enumeration in the dimensions of hosts, instances and time.  Special qualifiers may appear
       after a performance metric name to define the enumeration in each dimension.  For example,

           kernel.percpu.cpu.user :foo :bar #cpu0 @0..2

       defines 6 values corresponding to the time spent executing in user mode on CPU  0  on  the
       hosts ``foo'' and ``bar'' over the last 3 consecutive samples.  The default interpretation
       in the absence of : (host), # (instance) and @ (time) qualifiers is all instances  at  the
       most recent sample time for the default source of PCP performance metrics.

       Host  and  instance  names  that  do  not  follow  the  rules for variables in programming
       languages, ie. alphabetic optionally followed by  alphanumerics,  should  be  enclosed  in
       single quotes.

       Expression  evaluation  follows the law of ``least surprises''.  Where performance metrics
       have the semantics of a counter, pmie will automatically convert  to  a  rate  based  upon
       consecutive  samples and the time interval between these samples.  All numeric expressions
       are evaluated in double  precision,  and  where  appropriate,  automatically  scaled  into
       canonical units of ``bytes'', ``seconds'' and ``counts''.

       A rule is a special form of expression that specifies a condition or logical expression, a
       special operator (->) and actions to be performed when the condition is found to be true.

       The following table summarizes the basic pmie operators:

                   ┌────────────────┬────────────────────────────────────────────────┐
                   │   Operators    │                  Explanation                   │
                   ├────────────────┼────────────────────────────────────────────────┤
                   │+ - * /         │ Arithmetic                                     │
                   │< <= == >= > != │ Relational (value comparison)                  │
                   │! && ||         │ Boolean                                        │
                   │->              │ Rule                                           │
                   │rising          │ Boolean, false to true transition              │
                   │falling         │ Boolean, true to false transition              │
                   │rate            │ Explicit rate conversion (rarely required)     │
                   │instant         │ No automatic rate conversion (rarely required) │
                   └────────────────┴────────────────────────────────────────────────┘
       All operators are supported for numeric-valued  operands  and  expressions.   For  string-
       valued operands, namely literal string constants enclosed in double quotes or metrics with
       a data type of string (PM_TYPE_STRING), only the operators == and != are supported.

       The rate and instant operators are the logical inverse of one another,  so  an  arithmetic
       expression  expr  is equal to rate instant expr.  The more useful cases involve using rate
       with a metric that is not a counter to determine the rate of change over time  or  instant
       with  a  metric that is a counter to determine if the current value is above or below some
       threshold.

       Aggregate operators may be used to aggregate or summarize along one dimension  of  a  set-
       valued  expression.   The following aggregate operators map from a logical expression to a
       logical expression of lower dimension.

                  ┌─────────────────────────┬─────────────┬──────────────────────────┐
                  │       Operators         │    Type     │       Explanation        │
                  ├─────────────────────────┼─────────────┼──────────────────────────┤
                  │some_inst                │ Existential │ True if at least one set │
                  │some_host                │             │ member is true in the    │
                  │some_sample              │             │ associated dimension     │
                  ├─────────────────────────┼─────────────┼──────────────────────────┤
                  │all_inst                 │ Universal   │ True if all set members  │
                  │all_host                 │             │ are true in the          │
                  │all_sample               │             │ associated dimension     │
                  ├─────────────────────────┼─────────────┼──────────────────────────┤
                  │N%_inst                  │ Percentile  │ True if at least N       │
                  │N%_host                  │             │ percent of set members   │
                  │N%_sample                │             │ are true in the          │
                  │                         │             │ associated dimension     │
                  └─────────────────────────┴─────────────┴──────────────────────────┘
       The  following  instantial  operators  may be used to filter or limit a set-valued logical
       expression,  based  on  regular  expression  matching  of  instance  names.   The  logical
       expression  must be a set involving the dimension of instances, and the regular expression
       is of the form used by egrep(1) or the Extended Regular Expressions of regcomp(3).

                       ┌─────────────┬──────────────────────────────────────────┐
                       │ Operators   │               Explanation                │
                       ├─────────────┼──────────────────────────────────────────┤
                       │match_inst   │ For each value of the logical expression │
                       │             │ that is ``true'', the result is ``true'' │
                       │             │ if the associated instance name matches  │
                       │             │ the regular expression.  Otherwise the   │
                       │             │ result is ``false''.                     │
                       ├─────────────┼──────────────────────────────────────────┤
                       │nomatch_inst │ For each value of the logical expression │
                       │             │ that is ``true'', the result is ``true'' │
                       │             │ if the associated instance name does not │
                       │             │ match the regular expression.  Otherwise │
                       │             │ the result is ``false''.                 │
                       └─────────────┴──────────────────────────────────────────┘
       For example, the expression below will be ``true'' for disks attached to controllers 2  or
       3 performing more than 20 operations per second:
            match_inst "^dks[23]d" disk.dev.total > 20;

       The  following  aggregate  operators  map  from  an arithmetic expression to an arithmetic
       expression of lower dimension.

                   ┌─────────────────────────┬───────────┬──────────────────────────┐
                   │       Operators         │   Type    │       Explanation        │
                   ├─────────────────────────┼───────────┼──────────────────────────┤
                   │min_inst                 │ Extrema   │ Minimum value across all │
                   │min_host                 │           │ set members in the       │
                   │min_sample               │           │ associated dimension     │
                   ├─────────────────────────┼───────────┼──────────────────────────┤
                   │max_inst                 │ Extrema   │ Maximum value across all │
                   │max_host                 │           │ set members in the       │
                   │max_sample               │           │ associated dimension     │
                   ├─────────────────────────┼───────────┼──────────────────────────┤
                   │sum_inst                 │ Aggregate │ Sum of values across all │
                   │sum_host                 │           │ set members in the       │
                   │sum_sample               │           │ associated dimension     │
                   ├─────────────────────────┼───────────┼──────────────────────────┤
                   │avg_inst                 │ Aggregate │ Average value across all │
                   │avg_host                 │           │ set members in the       │
                   │avg_sample               │           │ associated dimension     │
                   └─────────────────────────┴───────────┴──────────────────────────┘
       The aggregate operators  count_inst,  count_host  and  count_sample  map  from  a  logical
       expression  to  an  arithmetic expression of lower dimension by counting the number of set
       members for which the expression is true in the associated dimension.

       For action rules, the following actions are defined:

                          ┌──────────┬────────────────────────────────────────┐
                          │Operators │              Explanation               │
                          ├──────────┼────────────────────────────────────────┤
                          │alarm     │ Raise a visible alarm with xconfirm(1) │
                          │print     │ Display on standard output             │
                          │shell     │ Execute with sh(1)                     │
                          │stomp     │ Send a STOMP message to a JMS server   │
                          │syslog    │ Append a message to system log file    │
                          └──────────┴────────────────────────────────────────┘
       Multiple actions may be separated by  the  &  and  |  operators  to  specify  respectively
       sequential  execution  (both  actions  are  executed)  and alternate execution (the second
       action will only be executed if the execution of the first action returns a non-zero error
       status.

       Arguments to actions are an optional suppression time, and then one or more expressions (a
       string is an expression in this context).  Strings appearing as arguments to an action may
       include  the  following  special selectors that will be replaced at the time the action is
       executed.

       %h  Host name(s) that make the left-most top-level expression in the condition true.

       %c  Connection specification string(s) or files for a PCP  tool  to  reach  the  hosts  or
           archives that make the left-most top-level expression in the condition true.

       %i  Instance(s) that make the left-most top-level expression in the condition true.

       %v  One  value  from the left-most top-level expression in the condition for each host and
           instance pair that makes the condition true.

       Note that expansion of the special selectors is done by repeating the whole argument  once
       for each unique binding to any of the qualifying special selectors.  For example if a rule
       were true for the host mumble with instances grunt and snort,  and  for  host  fumble  the
       instance puff makes the rule true, then the action
            ...
            -> shell myscript "Warning: %h:%i busy ";
       will  execute  myscript  with  the  argument  string  "Warning: mumble:grunt busy Warning:
       mumble:snort busy Warning: fumble:puff busy".

       By comparison, if the action
            ...
            -> shell myscript "Warning! busy:" " %h:%i";
       were executed under the same circumstances, then  myscript  would  be  executed  with  the
       argument string "Warning! busy: mumble:grunt mumble:snort fumble:puff".

       The semantics of the expansion of the special selectors leads to a common usage pattern in
       an action, where one argument is a constant (contains no  special  selectors)  the  second
       argument  contains the desired special selectors with minimal separator characters, and an
       optional third argument provides a constant postscript (e.g.  to  terminate  any  argument
       quoting  from  the  first  argument).   If necessary post-processing (eg. in myscript) can
       provide the necessary enumeration over each unique expansion of the string containing just
       the special selectors.

       For  complex  conditions,  the bindings to these selectors is not obvious.  It is strongly
       recommended that pmie be used in the debugging mode (specify the -W command line option in
       particular) during rule development.

BOOLEAN EXPRESSIONS

       pmie  expressions  that have the semantics of a Boolean, e.g.  foo.bar > 10 or some_inst (
       my.table < 0 ) are assigned the values true or false or unknown.  A value  is  unknown  if
       one  or  more  of  the  underlying metric values is unavailable, e.g.  pmcd(1) on the host
       cannot be contacted, the metric is not  in  the  PCP  archive,  no  values  are  currently
       available,  insufficient  values  have  been fetched to allow a rate converted value to be
       computed or insufficient values have been fetched to instantiate the  required  number  of
       samples in the temporal domain.

       Boolean  operators  follow  the  normal  rules  of  Kleene logic (aka 3-valued logic) when
       combining values that include unknown:

                               ┌────────────┬───────────────────────────┐
                               │            │             B             │
                               │  A and B   ├─────────┬───────┬─────────┤
                               │            │  truefalseunknown │
                               ├──┬─────────┼─────────┼───────┼─────────┤
                               │  │  truetruefalseunknown │
                               │  ├─────────┼─────────┼───────┼─────────┤
                               │A │  falsefalsefalsefalse  │
                               │  ├─────────┼─────────┼───────┼─────────┤
                               │  │ unknownunknownfalseunknown │
                               └──┴─────────┴─────────┴───────┴─────────┘
                                ┌────────────┬──────────────────────────┐
                                │            │            B             │
                                │  A or B    ├──────┬─────────┬─────────┤
                                │            │ truefalseunknown │
                                ├──┬─────────┼──────┼─────────┼─────────┤
                                │  │  truetruetruetrue   │
                                │  ├─────────┼──────┼─────────┼─────────┤
                                │A │  falsetruefalseunknown │
                                │  ├─────────┼──────┼─────────┼─────────┤
                                │  │ unknowntrueunknownunknown │
                                └──┴─────────┴──────┴─────────┴─────────┘
                                          ┌────────┬─────────┐
                                          │   A    │  not A  │
                                          ├────────┼─────────┤
                                          │ truefalse  │
                                          ├────────┼─────────┤
                                          │ falsetrue   │
                                          ├────────┼─────────┤
                                          │unknownunknown │
                                          └────────┴─────────┘

RULESETS

       The ruleset clause is used to define a set of rules and  actions  that  are  evaluated  in
       order  until  some  action is executed, at which point the remaining rules and actions are
       skipped until the ruleset is again scheduled for evaluation.  The keyword else is used  to
       separate  rules.   After  one  or  more  regular rules (with a predicate and an action), a
       ruleset may include an optional
            unknown -> action
       clause, optionally followed by a
            otherwise -> action
       clause.

       If all of the predicates in the rules evaluate to unknown and an unknown clause  has  been
       specified then action associated with the unknown clause will be executed.

       If  no  rule  predicate  is  true  and  the  unknown action is either not specified or not
       executed and an otherwise clause has been specified, then the action associated  with  the
       otherwise clause will be executed.

SCALE FACTORS

       Scale  factors  may  be appended to arithmetic expressions and force linear scaling of the
       value to canonical units.   Simple  scale  factors  are  constructed  from  the  keywords:
       nanosecond,  nanosec,  nsec,  microsecond,  microsec,  usec,  millisecond, millisec, msec,
       second, sec, minute, min, hour, byte,  Kbyte,  Mbyte,  Gbyte,  Tbyte,  count,  Kcount  and
       Mcount, and the operator /, for example ``Kbytes / hour''.

MACROS

       Macros are defined using expressions of the form:

            name = constexpr;

       Where name follows the normal rules for variables in programming languages, ie. alphabetic
       optionally followed by alphanumerics.  constexpr must be a constant expression,  either  a
       string  (enclosed  in  double quotes) or an arithmetic expression optionally followed by a
       scale factor.

       Macros are expanded when their name, prefixed by a dollar ($) appears  in  an  expression,
       and macros may be nested within a constexpr string.

       The following reserved macro names are understood.

       minute    Current minute of the hour.

       hour      Current hour of the day, in the range 0 to 23.

       day       Current day of the month, in the range 1 to 31.

       month     Current month of the year, in the range 0 (January) to 11 (December).

       year      Current year.

       day_of_week
                 Current day of the week, in the range 0 (Sunday) to 6 (Saturday).

       delta     Sample interval in effect for this expression.

       Dates  and  times  are  presented in the reporting time zone (see description of -Z and -z
       command line options above).

AUTOMATIC RESTART

       It is often useful for pmie processes to be started and stopped when  the  local  host  is
       booted  or  shutdown, or when they have been detected as no longer running (when they have
       unexpectedly exited for some reason).  Refer to pmie_check(1) for  details  on  automating
       this process.

EVENT MONITORING

       It  is common for production systems to be monitored in a central location.  Traditionally
       on UNIX systems this has been performed by the system log facilities - see logger(1),  and
       syslogd(1).   On  Windows,  communication  with  the  system  event log is handled by pcp-
       eventlog(1).

       pmie fits into this model when rules use the syslog  action.   Note  that  if  the  action
       string  begins with -p (priority) and/or -t (tag) then these are extracted from the string
       and treated in the same way as in logger(1) and pcp-eventlog(1).

       However, it is common to have other event monitoring frameworks also, into which  you  may
       wish  to  incorporate performance events from pmie.  You can often use the shell action to
       send events to these frameworks, as they usually provide their  a  program  for  injecting
       events into the framework from external sources.

       A  final  option  is use of the stomp (Streaming Text Oriented Messaging Protocol) action,
       which allows pmie to connect to a central JMS (Java  Messaging  System)  server  and  send
       events to the PMIE topic.  Tools can be written to extract these text messages and present
       them to operations people (via desktop popup windows,  etc).   Use  of  the  stomp  action
       requires  a  stomp configuration file to be setup, which specifies the location of the JMS
       server host, port number, and username/password.

       The format of this file is as follows:

            host=messages.sgi.com   # this is the JMS server (required)
            port=61616              # and its listening here (required)
            timeout=2               # seconds to wait for server (optional)
            username=joe            # (required)
            password=j03ST0MP       # (required)
            topic=PMIE              # JMS topic for pmie messages (optional)

       The  timeout  value  specifies  the  time  (in  seconds)  that  pmie   should   wait   for
       acknowledgements  from  the  JMS  server after sending a message (as required by the STOMP
       protocol).  Note that on startup, pmie will wait indefinitely for a connection,  and  will
       not  begin rule evaluation until that initial connection has been established.  Should the
       connection to the JMS server be lost at any time while pmie is running, pmie will  attempt
       to reconnect on each subsequent truthful evaluation of a rule with a stomp action, but not
       more than once per minute.  This is to avoid contributing to network congestion.  In  this
       situation, where the STOMP connection to the JMS server has been severed, the stomp action
       will return a non-zero error value.

FILES

       $PCP_DEMOS_DIR/pmie/*
                 annotated example rules
       $PCP_VAR_DIR/pmns/*
                 default PMNS specification files
       $PCP_TMP_DIR/pmie
                 pmie maintains files in this directory to identify the  running  pmie  instances
                 and  to  export  runtime  information  about each instance - this data forms the
                 basis of the pmcd.pmie performance metrics
       $PCP_PMIECONTROL_PATH
                 the default set of pmie instances to start at boot time - refer to pmie_check(1)
                 for details

BUGS

       The  lexical  scanner  and  parser  will  attempt  to  recover after an error in the input
       expressions.  Parsing resumes after skipping input up to the next semi-colon (;),  however
       during  this  skipping  process  the  scanner  is  ignorant of comments and strings, so an
       embedded semi-colon may cause parsing to resume at an unexpected place.  This behavior  is
       largely  benign, as until the initial syntax error is corrected, pmie will not attempt any
       expression evaluation.

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).

       When  executing  shell  actions,  pmie  overrides  two  variables  - IFS and PATH - in the
       environment of the child process.  IFS is set to "\t\n".  The PATH is set to a combination
       of  a  default  path  for all platforms ("/usr/sbin:/sbin:/usr/bin:/usr/sbin") and several
       configurable components.  These are (in this  order):  $PCP_BIN_DIR,  $PCP_BINADM_DIR  and
       $PCP_PLATFORM_PATHS.

       When  executing  popup alarm actions, pmie will use the value of $PCP_XCONFIRM_PROG as the
       visual notification program to run.  This is  typically  set  to  pmconfirm(1),  a  cross-
       platform dialog box.

UNIX SEE ALSO

       logger(1).

WINDOWS SEE ALSO

       pcp-eventlog(1).

SEE ALSO

       PCPIntro(1),  pmcd(1),  pmconfirm(1), pmdumplog(1), pmieconf(1), pmie_check(1), pminfo(1),
       pmlogger(1), pmval(1), PMAPI(3), pcp.conf(5) and pcp.env(5).

USER GUIDE

       For a more complete description of the pmie language, refer to  the  Performance  Co-Pilot
       Users and Administrators Guide.  This is available online from:
           http://www.pcp.io/doc/pcp-users-and-administrators-guide.pdf