1PMLC(1) General Commands Manual PMLC(1)
2
6 pmlc - configure active Performance Co-Pilot pmlogger(s) interactively
7
9 pmlc [-eiPz?] [-h host] [-n pmnsfile] [-p port] [-Z timezone] [pid]
10
12 pmlc may be used to change those metrics and instances which a pmlog‐
13 ger(1) writes to a Performance Co-Pilot archive (see PCPIntro(1)), the
14 frequency with which the metrics are collected and whether the logging
15 is mandatory, advisory, on or off. It also reports the current logging
16 status of metrics and instances. pmlc may be used to control pmlogger
17 instances on remote hosts as well as those on the local host.
18 Normally pmlc operates on the distributed Performance Metrics Name
20 Space (PMNS), however if the -n option is specified an alternative
21 local PMNS is loaded from the file pmnsfile.
22 If the -P option is specified, pmlc will attempt to start with a con‐
24 nection to the primary pmlogger on the local host. If the -p option is
25 specified, then pmlc will attempt to start with a connection to the
26 pmlogger on this TCP/IP port. Alternatively, if pid is specified, a
27 connection to the pmlogger instance with that process id will be
28 attempted on startup. The -h option may only be used if -P, -p port or
29 a pid is also specified. In that case pmlc will initially connect to
30 the specified (remote) pmlogger instance on host rather than the local
31 host. If the connection to the specified pmlogger instance cannot be
32 established, pmlc will start with no connection. These options typi‐
33 cally allow the same file of pmlc commands to be directed to multiple
34 pmlogger instances by varying the command line arguments. Note that
35 -P, -p port, pid and -h are used only when making an initial connection
36 to a pmlogger instance. They are not used as defaults if subsequent
37 connections are made interactively (see the connect command below).
38 By default, pmlc reports the time of day according to the local time‐
40 zone on the system where pmlc is run. The -Z option changes the time‐
41 zone to timezone in the format of the environment variable TZ as
42 described in environ(7). The -z option changes the timezone to the
43 timezone of the pmlogger instance from which information is being
44 obtained. Only one of -z or -Z may be specified.
45 If standard input is from a tty, pmlc is interactive, with prompts.
47 The -i flag may be used to force interactive behavior, and is typically
48 used in conjunction with -e to echo all command input on standard out‐
49 put.
50
52 The following commands may be used:
53 show [ loggers ] [ @host ]
55 Displays the process identities of all pmlogger instances running
56 on the local host (or host, if specified). The primary pmlogger
57 pid is parenthesized because it can be referred to as "primary" as
58 well as by its pid.
59 connect pid [ @host ]
61 connect primary [ @host ]
62 Connects pmlc to the specified pmlogger process. Any existing con‐
63 nection to a pmlogger instance is closed first. Each pmlogger
64 instance will accept at most one connection at a time, so if the
65 connection is successfully established, your pmlc will be the only
66 one controlling the pmlogger instance it is connected to.
67 new volume
69 This command works only while a connection to a pmlogger instance
70 is established. It tells the pmlogger to close the current volume
71 of the log and open a new volume. Closed volumes may be archived,
72 e.g. as part of a regular log management procedure to control the
73 size of the physical log files.
74 status
76 This command works only while a connection to a pmlogger instance
77 is established. It prints information about the state of the
78 pmlogger instance and its associated log.
79 timezone local | logger | "timezone"
81 This command sets the time zone used when times are printed. local
82 means use the time zone of the machine that pmlc is running on.
83 logger means use the time zone of the machine where the pmlogger
84 instance is running. Alternatively an explicit timezone enclosed
85 in quotes may be supplied (refer to TZ in environ(7) for details).
86 The default time zone is local unless one of the -z or -Z options
87 has been supplied on the command line.
88 flush
90 This command works only while a connection to a pmlogger instance
91 is established, and requests the pmlogger instance to flush to disk
92 all buffers associated with the current archive. For old-timers,
93 sync is a synonym for flush. In current versions of pmlogger(1)
94 all writes are unbuffered and aligned with the logical records in
95 the external files, so this command achieves nothing, but is
96 retained for backwards compatibility.
97 disconnect
99 Disconnect pmlc from the current pmlogger instance, if any.
100 sleep delay
102 Pause pmlc for delay milliseconds. This may be helpful in scripted
103 uses of pmlc to allow the current pmlogger instance to make
104 progress on recent requests before interrogating the status.
105 help
107 Displays a summary of the available commands.
108 h and ? are synonyms for help.
109 quit
111 Exits from pmlc.
112 The remaining commands query and change the logging state of metrics
114 and instances. They will work only if pmlc has a connection to a
115 pmlogger instance. Metrics may be specified as fully qualified names
116 (e.g. hinv.ncpu) or subtrees of the PMNS (e.g. hinv) which are expanded
117 to include all metrics in the subtree (e.g. hinv.ncpu, hinv.cpuclock,
118 etc.). Lists of metrics may be specified by enclosing them in braces
119 with spaces or a comma between metrics (e.g. {hinv.ncpu hinv.ndisk}).
120 Subtrees of metrics may be included in such lists.
121 Each individual metric specification may be further qualified with a
123 space or comma separated list of instances in square brackets (e.g.
124 kernel.all.load["1 minute", "5 minute"]). External instance names or
125 numeric internal instance identifiers or both may be used in the same
126 list (e.g. sample.colour.[red,1,"blue"]). If an instance qualification
127 is applied to a subtree of the PMNS all of the metrics in the subtree
128 must have the same instance domain. Instance qualifications may not be
129 applied to entire lists of metrics but may appear inside such lists.
130 If no instances are specified for a metric, all instances are used.
132 All instances means all instances available at the time the pmlogger
133 instance in question fetches the metrics for logging. If an instance
134 domain changes over time this is not always the same as the set of
135 instances displayed by pmlc, which can only display the currently
136 available instances. To prevent unintentional errors, only the
137 instances that are currently available to pmlc may appear in instance
138 specifications.
139 query metriclist
141 The current logging state of each metric (and instances, where
142 applicable) in metriclist is displayed. This includes the logging
143 state (e.g. on, maybe, off) and the logging interval for each met‐
144 ric (and instance) requested. The following abbreviations pertain‐
145 ing to metrics (and instances) may appear in the output: adv, advi‐
146 sory; mand, mandatory; nl, not in the log; na, in the log but not
147 currently available from its Performance Metrics Domain Agent
148 (PMDA). Where appropriate, an instance name will appear last on a
149 line preceded by its numeric internal instance identifier.
150 [ log ] mandatory on interval metriclist
152 This form of the log command turns on logging for the metrics (and
153 any instances) in metriclist. interval specifies how often the
154 specified metrics/instances should be logged. once indicates that
155 the metrics/instances should appear at most once in the log. More
156 often one would use the optional keyword every followed by a posi‐
157 tive number and one of millisecond (or msec), second (or sec),
158 minute (or min), hour or their plurals.
159 Note that the keyword default which may be used for the default
160 interval in a pmlogger(1) configuration file cannot be used in
161 pmlc.
162 Internal limitations require the interval to be less than (approxi‐
163 mately) 74 hours. An interval value of zero is a synonym for once.
164 [ log ] mandatory off metriclist
166 This tells the pmlogger instance not to log any of the met‐
167 rics/instances in metriclist.
168 [ log ] mandatory maybe metriclist
170 This tells the pmlogger instance to honor any subsequent advisory
171 logging requests for the metrics/instances in metriclist. If the
172 current logging state of the metrics/instances is mandatory (either
173 on or off) the new state will be set to maybe (effectively advisory
174 off). If the current state of the metrics/instances is already
175 advisory (either on or off) the state(s) for the metrics/instances
176 will remain as they are.
177 [ log ] advisory on interval metriclist
179 [ log ] advisory off metriclist
180 Advisory logging is only applicable if the last logging state spec‐
181 ified for a metric/instance was "mandatory maybe" (which permits
182 subsequent advisory logging control) or if the logging state is
183 already advisory. These two statements turn advisory logging on or
184 off (respectively) for the specified metrics/instances.
185 The interpretation for interval is as above for the mandatory case.
186 There is no continuation character required for commands that span
188 lines.
189 The word at may be used interchangeably with @.
191 A request to log all instances of a metric will supersede any prior
193 request to log either all or specific instances of a metric (if the
194 request specifies a permissible transition in the logging state). A
195 request to log specific instances of a metric when all instances of a
196 metric are already being logged is refused by pmlogger.
197
199 The available command line options are:
200 -e, --echo
202 Echo all command input on standard output.
203 -h host, --host=host
205 Connect pmlogger on host, rather than on the default localhost.
206 -i, --interactive
208 Force interactive behavior.
209 -n pmnsfile, --namespace=pmnsfile
211 Load an alternative Performance Metrics Name Space (PMNS(5)) from
212 the file pmnsfile.
213 -p port, --port=port
215 Connect to the primary pmlogger on TCP/IP port port.
216 -P, --primary
218 Connect to the primary pmlogger.
219 -z, --logzone
221 Use local time of the pmlogger as the reporting timezone.
222 -Z timezone, --timezone=timezone
224 Use timezone for the date and time. Timezone is in the format of
225 the environment variable TZ as described in environ(7).
226 -?, --help
228 Display usage message and exit.
229
231 pmlc may have restricted access to and control over pmlogger(1) pro‐
232 cesses.
233 If a pmlogger(1) is unable to export its control information to the
235 local pmcd(1), then that pmlogger(1) cannot cannot be connected to nor
236 controlled by pmlc. In practice, this means the pmlogger(1) process
237 has to be owned by the user ``pcp'' and/or the group ``pcp''. If
238 pmlogger(1) is running on the host ``foo'' then use ``pminfo -f -h foo
239 pmcd.pmlogger'' to verify that the pmlogger(1) of interest is known to
240 pmcd(1), alternatively pmlogger(1) instances that are not reported from
241 the pmlc show loggers @foo command are not known to pmcd(1) on the host
242 ``foo''.
243 If pmlogger(1) is launched with a configuration file that contains an
245 [access] section, then pmlc will be unable to connect to that pmlog‐
246 ger(1) unless the access controls allow some access from the host where
247 pmlc is being run. Minimally this requires the enquire access to be
248 permitted in the pmlogger(1) access control section.
249 If pmlc is able to connect to the pmlogger(1) of interest, then the
251 following table summarizes the permissions needed to perform different
252 pmlc commands:
253 ┌──────────────────┬───────────────────────────────────────┐
255 │ pmlc command │ Required pmlogger access │
256 ├──────────────────┼───────────────────────────────────────┤
257 │show loggers │ Any │
258 │connect │ Any of enquire, advisory or mandatory │
259 │status │ Any of enquire, advisory or mandatory │
260 │query ... │ Any of enquire, advisory or mandatory │
261 │disconnect │ Any │
262 │log advisory ... │ advisory │
263 │log mandatory ... │ mandatory │
264 │new volume │ mandatory │
265 └──────────────────┴───────────────────────────────────────┘
267 If all instances of a metric are being logged and a request is made to
268 log specific instances of the metric with the same state and frequency,
269 the request may appear to succeed, even though pmlogger has refused the
270 request. This is not normally a problem, as the required information
271 will still be placed into the log by pmlogger.
272 However in the case where the metric is to be logged once, the outcome
274 is not what might be expected. When pmlogger receives a request to log
275 a metric once, it places the current value(s) of the metric into the
276 log as soon as it can, regardless of whether the metric is already in
277 the log. This may be used to force values into the log. When a
278 request to log specific instances of a metric arrives and is refused
279 because all instances of the metric are already being logged, pmlogger
280 does not place values for the instances requested into the log. It
281 returns the current logging state for each instance requested to pmlc.
282 The requested and returned states are identical, so pmlc doesn't raise
283 an error as it should.
284 To ensure that only certain instances of a metric are being logged, one
286 should always turn off logging for all instances of the metric prior to
287 turning on logging for the specific instances required.
288
290 Most error or warning messages are self-explanatory. A message of the
291 form
292 Warning: unable to change logging state for...
293 followed by a list of metrics (and possibly instances) indicates that
294 pmlogger refused the request for the metrics (and instances) that
295 appear. Any metrics (and instances) that were specified but do not
296 appear in the message have had their logging state updated successfully
297 (no news is good news). Usually this warning results from requesting
298 advisory logging when a mandatory control is already in place, or
299 requesting logging for specific instances when all instances are
300 already being logged.
301
303 If the PMLOGGER_REQUEST_TIMEOUT environment variable is not set or set
304 to 0 (zero), then pmlc will block until a connection is established
305 with pmlogger(1) on the requested port. If PMLOGGER_REQUEST_TIMEOUT is
306 set to a value greater than zero, then pmlc will fail with an error
307 after that many seconds if a connection isn't established. This may be
308 used by administrative scripts such as pmlogger_daily(1) to poll pmlog‐
309 ger when is starting up until it is ready and listening on it's control
310 port.
311
313 Environment variables with the prefix PCP_ are used to parameterize the
314 file and directory names used by PCP. On each installation, the file
315 /etc/pcp.conf contains the local values for these variables. The
316 $PCP_CONF variable may be used to specify an alternative configuration
317 file, as described in pcp.conf(5).
318
320 PCPIntro(1), pmcd(1), pmdumplog(1), pmlogger(1), pcp.conf(5),
321 pcp.env(5), PMNS(5) and environ(7).
322Performance Co-Pilot PCP PMLC(1)