1PMWEBAPI(3) Library Functions Manual PMWEBAPI(3)
2
6 PMWEBAPI - introduction to the Performance Metrics Web Application Pro‐
7 gramming Interface
8
10 GET /metrics
11 GET /series/...
12 GET /search/...
13 GET /pmapi/...
14
16 #include <pcp/pmwebapi.h>
17 ... assorted routines ...
19 cc ... -lpcp_web -lpcp
21
23 The PMWEBAPI is a collection of interfaces providing Performance Co-
24 Pilot services for web applications. It consists of APIs for web
25 applications querying and analysing both live and historical perfor‐
26 mance data, as well as APIs used by web servers.
27 The usual HTTP URL-encoded optional parameter rules apply and PMWEBAPI
29 REST requests always follow the convention:
30 /api/endpoint?parameter1=value1¶meter2=value2
32 Examples in all following sections use the curl(1) command line utility
34 with a local pmproxy(1) server listening on port 44322 (default port).
35 The pmjson(1) utility is used to neatly format any JSON output, as
36 opposed to the compact (minimal whitespace) form provided by default.
37 The examples in the scalable time series section use historical data
38 recorded by the pmlogger(1) service, in conjunction with a local redis-
39 server(1).
40
42 Exporting of live performance metrics in an Open Metrics compatible
43 format (as described at https://openmetrics.io and popularized by the
44 https://prometheus.io project) is available.
45 GET /metrics
47 ┌───────────┬─────────┬────────────────────────────────────────────────┐
48 │Parameters │ Type │ Explanation │
49 ├───────────┼─────────┼────────────────────────────────────────────────┤
50 │names │ string │ Comma-separated list of metric names │
51 │times │ boolean │ Append sample times (milliseconds since epoch) │
52 └───────────┴─────────┴────────────────────────────────────────────────┘
53 Fetches current values and metadata for all metrics, or only metrics
54 indicated by a comma-separated list of names.
55 For all numeric metrics with the given NAME prefixes, create an Open
57 Metrics (Prometheus) text export format giving their current value and
58 related metadata.
59 The response has plain text type rather than JSON commonly used else‐
61 where in the REST API. This format can be injested by many open source
62 monitoring tools, including Prometheus and pmdaopenmetrics(1).
63 The native PCP metric metadata (metric name, type, indom, semantics and
65 units) is first output for each metric with # PCP prefix. The metadata
66 reported is of the form described on pmTypeStr(3), pmInDomStr(3),
67 pmSemStr(3) and pmUnitsStr(3) respectively. If the pmUnitsStr(3) units
68 string is empty, then none is output. The units metadata string may
69 contain spaces and extends to the end of the line.
70 PCP metric names are mapped so that the . separators are exchanged with
72 _ (':' in back-compatibility mode, where "# PCP" is the identifying
73 line suffix). Both metric labels and instances are represented as
74 Prometheus labels, with external instance names being quoted and the
75 flattened PCP metric hierarchy being presented with each value.
76 $ curl -s http://localhost:44322/metrics?names=proc.nprocs,kernel.pernode.cpu.intr,filesys.blocksize
78 # PCP5 proc.nprocs 3.8.99 u32 PM_INDOM_NULL instant none
80 # HELP proc_nprocs instantaneous number of processes
81 # TYPE proc_nprocs gauge
82 proc_nprocs {hostname="app1"} 7
83 # PCP5 kernel.pernode.cpu.intr 60.0.66 u64 60.19 counter millisec
85 # HELP kernel_pernode_cpu_intr total interrupt CPU [...]
86 # TYPE kernel_pernode_cpu_intr counter
87 kernel_pernode_cpu_intr{hostname="app1",instname="node0"} 25603
88 # PCP5 filesys.blocksize 60.5.9 u32 60.5 instant byte
90 # HELP filesys_blocksize Size of each block on mounted file[...]
91 # TYPE filesys_blocksize gauge
92 filesys_blocksize{hostname="app1",instname="/dev/sda1"} 4096
93 filesys_blocksize{hostname="app1",instname="/dev/sda2"} 4096
94
96 The fast, scalable time series query capabilities provided by the pm‐
97 series(1) command are also available through a REST API. These queries
98 provide access to performance data (metric metadata and values) from
99 multiple hosts simultaneously, and in a fashion suited to efficient re‐
100 trieval by any number of web applications.
101 All requests in this group can be accompanied by an optional client pa‐
103 rameter. The value passed in the request will be sent back in the re‐
104 sponse - all responses will be in JSON object form in this case, with
105 top level "client" and "result" fields.
106 GET /series/query - pmSeriesQuery(3)
108 ┌───────────┬────────┬────────────────────────────────────────────┐
109 │Parameters │ Type │ Explanation │
110 ├───────────┼────────┼────────────────────────────────────────────┤
111 │expr │ string │ Query string in pmseries(1) format │
112 │client │ string │ Request identifier sent back with response │
113 └───────────┴────────┴────────────────────────────────────────────┘
114 Performs a time series query for either matching identifiers, or match‐
115 ing identifiers with series of time-stamped values.
116 The query is in the format described in pmseries(1) and is passed to
118 the server via either the expr parameter (HTTP GET) or via the message
119 body (HTTP POST).
120 When querying for time series matches only, no time window options are
122 specified and matching series identifiers are returned in a JSON array.
123 $ curl -s 'http://localhost:44322/series/query?expr=disk.dev.read*' | pmjson
125 [
126 "9d8c7fb51ce160eb82e3669aac74ba675dfa8900",
127 "ddff1bfe286a3b18cebcbadc1678a68a964fbe9d",
128 "605fc77742cd0317597291329561ac4e50c0dd12"
129 ]
130 When querying for time series values as well, a time window must be
132 specified as part of the query string. The simplest form is to just
133 request the most recent sample.
134 $ curl -s 'http://localhost:44322/series/query?expr=disk.dev.read*[samples:1]' | pmjson
136 [
137 {
138 "series": "9d8c7fb51ce160eb82e3669aac74ba675dfa8900",
139 "instance": "c3795d8b757506a2901c6b08b489ba56cae7f0d4",
140 "timestamp": 1547483646.2147431,
141 "value": "12499"
142 }, {
143 "series": "ddff1bfe286a3b18cebcbadc1678a68a964fbe9d",
144 "instance": "6b08b489ba56cae7f0d4c3795d8b757506a2901c",
145 "timestamp": 1547485701.7431218,
146 "value": "1118623"
147 }, {
148 "series": "605fc77742cd0317597291329561ac4e50c0dd12",
149 "instance": "c3795d8b757506a2901c6b08b489ba56cae7f0d4",
150 "timestamp": 1547483646.2147431,
151 "value": "71661"
152 }
153 ]
154 GET /series/values - pmSeriesValues(3)
156 ┌───────────┬────────┬────────────────────────────────────────────┐
157 │Parameters │ Type │ Explanation │
158 ├───────────┼────────┼────────────────────────────────────────────┤
159 │series │ string │ Comma-separated list of series identifiers │
160 │client │ string │ Request identifier sent back with response │
161 ├───────────┼────────┼────────────────────────────────────────────┤
162 │samples │ number │ Count of samples to return │
163 │interval │ string │ Time between successive samples │
164 │start │ string │ Sample window start time │
165 │finish │ string │ Sample window end time │
166 │offset │ string │ Sample window offset │
167 │align │ string │ Sample time alignment │
168 │zone │ string │ Time window timezone │
169 └───────────┴────────┴────────────────────────────────────────────┘
170 Performs values retrievals for one or more time series identifiers.
171 The JSON response contains the same information as the pmseries
172 -q/--query option using any of the time window parameters described on
173 pmseries(1). If no time window parameters are specified, the single
174 most recent value observed is retrieved.
175 $ curl -s http://localhost:44322/series/values?series=605fc77742cd0317597291329561ac4e50c0dd12 | pmjson
177 [
178 {
179 "series": "605fc77742cd0317597291329561ac4e50c0dd12",
180 "timestamp": 1317633022959.959241041,
181 "value": "71660"
182 }
183 ]
184 GET /series/descs - pmSeriesDescs(3)
186 ┌───────────┬────────┬────────────────────────────────────────────┐
187 │Parameters │ Type │ Explanation │
188 ├───────────┼────────┼────────────────────────────────────────────┤
189 │series │ string │ Comma-separated list of series identifiers │
190 │client │ string │ Request identifier sent back with response │
191 └───────────┴────────┴────────────────────────────────────────────┘
192 Performs a descriptor lookup for one or more time series identifiers.
193 The JSON response contains the same information as the pmseries
194 -d/--desc option.
195 $ curl -s http://localhost:44322/series/descs?series=605fc77742cd0317597291329561ac4e50c0dd12 | pmjson
197 [
198 {
199 "series": "605fc77742cd0317597291329561ac4e50c0dd12",
200 "source": "f5ca7481da8c038325d15612bb1c6473ce1ef16f",
201 "pmid": "60.0.4",
202 "indom": "60.1",
203 "semantics": "counter",
204 "type": "u32",
205 "units": "count",
206 }
207 ]
208 GET /series/labels - pmSeriesLabels(3), pmSeriesLabelValues(3)
210 ┌───────────┬────────┬────────────────────────────────────────────┐
211 │Parameters │ Type │ Explanation │
212 ├───────────┼────────┼────────────────────────────────────────────┤
213 │series │ string │ Comma-separated list of series identifiers │
214 │match │ string │ Glob pattern string to match on all labels │
215 │name │ string │ Find all known label values for given name │
216 │names │ string │ Comma-separated list of label names │
217 │client │ string │ Request identifier sent back with response │
218 └───────────┴────────┴────────────────────────────────────────────┘
219 This command operates in one of three modes. It can perform a label
220 set lookup for one or more time series identifiers, when given the
221 series parameter). It can produce a list of all known label names, in
222 the absence of name, names or series parameters. The JSON responses
223 for these modes contains the same information as the pmseries
224 -l/--labels option.
225 Alternatively, it can produce a list of all known label values for a
227 given label name or names. The JSON response for this mode contains
228 the same information as the pmseries -v/--values option.
229 $ curl -s http://localhost:44322/series/labels?series=605fc77742cd0317597291329561ac4e50c0dd12 | pmjson
231 [
232 {
233 "series": "605fc77742cd0317597291329561ac4e50c0dd12",
234 "labels": {
235 "agent": "linux",
236 "domainname": "acme.com",
237 "groupid": 1000,
238 "hostname": "www.acme.com",
239 "latitude": -25.28496,
240 "longitude": 152.87886,
241 "machineid": "295b16e3b6074cc8bdbda8bf96f6930a",
242 "platform": "dev",
243 "userid": 1000
244 }
245 }
246 ]
247 Alternatively, with no name, names or series parameters, return the
249 list of all known label names.
250 $ curl -s http://localhost:44322/series/labels | pmjson
252 [
253 "agent",
254 "appversion",
255 "domainname",
256 "groupid",
257 "hostname",
258 "jobid",
259 "latitude",
260 "longitude",
261 "machineid",
262 "platform",
263 "userid"
264 ]
265 Use the name or names parameters to find all possible label values for
267 the given name(s).
268 $ curl -s http://localhost:44322/series/labels?names=hostname,domainname | pmjson
270 {
271 "hostname": [ "app", "nas" ],
272 "domainname": [ "acme.com" ]
273 }
274 GET /series/metrics - pmSeriesMetrics(3)
276 ┌───────────┬────────┬────────────────────────────────────────────┐
277 │Parameters │ Type │ Explanation │
278 ├───────────┼────────┼────────────────────────────────────────────┤
279 │series │ string │ Comma-separated list of series identifiers │
280 │match │ string │ Glob pattern string to match on all names │
281 │client │ string │ Request identifier sent back with response │
282 └───────────┴────────┴────────────────────────────────────────────┘
283 Performs a metric name lookup for one or more time series identifiers.
284 The JSON response contains the same information as the pmseries
285 -m/--metrics option.
286 $ curl -s http://localhost:44322/series/metrics?series=605fc77742cd0317597291329561ac4e50c0dd12 | pmjson
288 [
289 {
290 "series": "605fc77742cd0317597291329561ac4e50c0dd12",
291 "name": "disk.dev.read_bytes"
292 }
293 ]
294 Alternatively, with no series argument, this request will return the
296 list of all known metric names.
297 $ curl -s http://localhost:44322/series/metrics | pmjson
299 [
300 "disk.dev.read",
301 "disk.dev.read_bytes",
302 "disk.dev.read_merge",
303 "kernel.all.load",
304 "kernel.all.pswitch",
305 ...
306 ]
307 GET /series/sources - pmSeriesSources(3)
309 ┌───────────┬────────┬─────────────────────────────────────────────┐
310 │Parameters │ Type │ Explanation │
311 ├───────────┼────────┼─────────────────────────────────────────────┤
312 │series │ string │ Comma-separated list of source identifiers │
313 │match │ string │ Glob pattern string to match on all sources │
314 │client │ string │ Request identifier sent back with response │
315 └───────────┴────────┴─────────────────────────────────────────────┘
316 Performs a lookup for one or more time series sources, returning an ar‐
317 ray of all PMAPI context names used to access the time series from that
318 source. The JSON response contains the same information as the pm‐
319 series -S/--source option.
320 $ curl -s http://localhost:44322/series/sources?source=2cd6a38f9339f2dd1f0b4775bda89a9e7244def6 | pmjson
322 [
323 {
324 "source": "2cd6a38f9339f2dd1f0b4775bda89a9e7244def6",
325 "context": [
326 "/var/log/pcp/pmlogger/acme",
327 "www.acme.com"
328 ]
329 }
330 ]
331 GET /series/instances - pmSeriesInstances(3)
333 ┌───────────┬────────┬───────────────────────────────────────────────┐
334 │Parameters │ Type │ Explanation │
335 ├───────────┼────────┼───────────────────────────────────────────────┤
336 │series │ string │ Comma-separated list of series identifiers │
337 │match │ string │ Glob pattern string to match on all instances │
338 │client │ string │ Request identifier sent back with response │
339 └───────────┴────────┴───────────────────────────────────────────────┘
340 Provide instance identifiers and names for one or more time series
341 identifiers. The JSON response contains the same information as the
342 pmseries -i/--instance option.
343 $ curl -s http://localhost:44322/series/instances?series=605fc77742cd0317597291329561ac4e50c0dd12 | pmjson
345 [
346 {
347 "series": "605fc77742cd0317597291329561ac4e50c0dd12",
348 "source": "97261ac7742cd4e50c0d03175913295d12605fc7",
349 "instance": "c3795d8b757506a2901c6b08b489ba56cae7f0d4"
350 "id": 1,
351 "name": "sda",
352 }, {
353 "series": "605fc77742cd0317597291329561ac4e50c0dd12",
354 "source": "97261ac7742cd4e50c0d03175913295d12605fc7",
355 "instance": "57506a2901c6b08b489ba56cae7f0d4c3795d8b7"
356 "id": 2,
357 "name": "sdb",
358 }
359 ]
360 Alternatively, with no series argument, this request will return the
362 list of all known instance names.
363 $ curl -s http://localhost:44322/series/instances | pmjson
365 [
366 "1 minute",
367 "5 minute",
368 "15 minute",
369 "cpu0",
370 "cpu1",
371 "cpu2",
372 "cpu3",
373 "node0",
374 "node1",
375 "sda",
376 "sdb",
377 ...
378 ]
379 GET /series/load - pmSeriesLoad(3)
381 ┌───────────┬────────┬────────────────────────────────────────────┐
382 │Parameters │ Type │ Explanation │
383 ├───────────┼────────┼────────────────────────────────────────────┤
384 │expr │ string │ Source load string in pmseries(1) format │
385 │client │ string │ Request identifier sent back with response │
386 └───────────┴────────┴────────────────────────────────────────────┘
387 Load time series performance data from the specified source into the
388 redis-server cache. This request is equivalent to the pmseries
389 -l/--load option.
390 $ curl -s http://localhost:44322/series/load?expr={source.name:"/var/log/pcp/pmlogger/acme"}
392 {
393 "success": true
394 }
395
397 The full text search capabilities provided by the pmsearch(1) command
398 are also available through a REST API. These queries provide access to
399 an index over performance metric names, instances, instance domains and
400 help text, suitable for a metric search engine, and in a fashion suited
401 to efficient querying by any number of web applications.
402 In order to use this functionality, the optional RediSearch module must
404 be loaded in the redis-server at the time pmproxy is started, such that
405 metrics, instances and help text it discovers can be automatically in‐
406 dexed.
407 GET /search/text - pmSearchTextQuery(3)
410 ┌───────────┬────────┬─────────────────────────────────────────────┐
411 │Parameters │ Type │ Explanation │
412 ├───────────┼────────┼─────────────────────────────────────────────┤
413 │query │ string │ Query string in pmsearch(1) format │
414 │highlight │ fields │ Include matching markup in response fields │
415 │offset │ number │ Result offset cursor for pagination │
416 │limit │ number │ Maximum results to include in response │
417 │field │ fields │ Queried fields (defaults to all) │
418 │return │ fields │ Fields to actually return (defaults to all) │
419 │type │ types │ Entity types to filter (defaults to all) │
420 └───────────┴────────┴─────────────────────────────────────────────┘
421 Performs a text search query across metrics and instance domains - all
422 forms of names and help texts.
423 The mandatory search string is further described in pmsearch(1) and is
425 passed to the server via the query parameter (HTTP GET).
426 $ curl -s http://localhost:44322/search/text?query=halt | pmjson
428 {
429 "total": 2,
430 "offset": 0,
431 "limit": 10,
432 "elapsed": 0.000504,
433 "results": [
434 {
435 "name": "kvm.halt_exits",
436 "type": "metric",
437 "indom": "95.0.4",
438 "oneline": "Number of guest exits due to halt calls.",
439 "helptext": "This type of exit is usually seen when a guest is idle."
440 },
441 {
442 "name": "kvm.halt_wakeup",
443 "type": "metric",
444 "indom": "95.0.6",
445 "oneline": "Number of wakeups from a halt.",
446 }
447 ]
448 }
449 The available search entity types are metric, indom and instance.
451 Query parameters highlight and field take name, oneline and helptext.
452 Query parameter return takes name, type, oneline, helptext, indom.
454 There is typically both a name and help text associated with metrics.
455 Contents of these are then matched against query. An instance domain
456 has help text and a numeric identifier, while instances have a name on‐
457 ly (which can be searched).
458 GET /search/suggest - pmSearchTextSuggest(3)
460 ┌───────────┬────────┬────────────────────────────────────┐
461 │Parameters │ Type │ Explanation │
462 ├───────────┼────────┼────────────────────────────────────┤
463 │query │ string │ Search query for search engine │
464 │limit │ number │ Max results to include in response │
465 └───────────┴────────┴────────────────────────────────────┘
466 Provides search query suggestions, that is, metric and instance names.
467 The mandatory search string is further described in pmsearch(1) and is
469 passed to the server via the query parameter (HTTP GET).
470 $ curl -s http://localhost:44322/search/suggest?query=disk&limit=4 | pmjson
472 [
473 "disk.all.avactive",
474 "disk.all.aveq",
475 "disk.all.blkread",
476 "disk.all.blktotal"
477 ]
478 GET /search/indom - pmSearchTextInDom(3)
480 ┌───────────┬────────┬─────────────────────────────────────┐
481 │Parameters │ Type │ Explanation │
482 ├───────────┼────────┼─────────────────────────────────────┤
483 │query │ string │ Target indom for search engine │
484 │offset │ number │ Result offset cursor for pagination │
485 │limit │ number │ M results to include in response │
486 └───────────┴────────┴─────────────────────────────────────┘
487 Provides all entities (instances, metrics) related to indom, including
488 itself, that is passed to the server via the query parameter.
489 GET /search/info - pmSearchInfo(3)
491 Provides metrics relating to operation of the search engine, in partic‐
492 ular showing document and text record counts.
493 $ curl -s http://localhost:44322/search/info | pmjson
495 {
496 "docs": 1589,
497 "terms": 3855,
498 "records": 116831,
499 "records_per_doc_avg": 73.52,
500 "bytes_per_record_avg": 6.36,
501 "inverted_sz_mb": 0.71,
502 "inverted_cap_mb": 0.00,
503 "inverted_cap_ovh": 0.00,
504 "skip_index_size_mb": 0.00,
505 "score_index_size_mb": 0.00,
506 "offsets_per_term_avg": 9.41,
507 "offset_bits_per_record_avg": 8.00
508 }
509
511 The live performance collection facilities available from pmcd(1) can
512 also be accessed through a REST API.
513 All requests are performed on the web server host by default, unless
515 either a hostspec or context parameter is provided. hostname can be
516 used in place of hostspec.
517 Context identifiers are used as a persistent way to refer to PMAPI con‐
519 texts across related web requests. These contexts expire after a con‐
520 figurable period of disuse, and are either explicitly allocated using
521 the /pmapi/context interface, or implicitly allocated using other in‐
522 terfaces.
523 The timeout interval is configurable at context creation time, and as
525 such the polltime parameter can be used anywhere the hostspec is speci‐
526 fied. It sets the context timeout in terms of length of inactive time.
527 The unit for the timeout value is seconds and the default is 5.
528 To specify a specific existing context in any PMAPI web request, the
530 endpoints can be accessed with either the context parameter or embedded
531 in the endpoint URL itself, such as /pmapi/[number]/fetch.
532 GET /pmapi/context - pmNewContext(3)
534 ┌────────────┬────────┬────────────────────────────────────────────────┐
535 │Parameters │ Type │ Explanation │
536 ├────────────┼────────┼────────────────────────────────────────────────┤
537 │hostspec │ string │ Host specification as described in PCPIntro(1) │
538 │polltimeout │ number │ Seconds of inactivity before closing context │
539 │client │ string │ Request identifier sent back with response │
540 └────────────┴────────┴────────────────────────────────────────────────┘
541 To create a context for live sampling, a web client can access any
542 /pmapi URL (optionally using the hostspec or context parameter). If no
543 context exists, a new one will be created for that web client, and its
544 identifier returned for future accesses.
545 However, /pmapi/context is provided as a dedicated URL for applications
547 wishing to explicitly create the contexts they use.
548 If successful, the server responds with a HTTP 200 (OK) code and JSON
550 message body of the form:
551 $ curl -s http://localhost:44322/pmapi/context?hostspec=www.acme.com&polltime=500 | pmjson
553 {
554 "context": 348734,
555 "source": "05af7f3eb840277fd3cfa91f90ef0067199743c",
556 "hostspec": "www.acme.com",
557 "labels": {
558 "domainname": "acme.com",
559 "groupid": 1000,
560 "hostname": "www.acme.com",
561 "machineid": "295b7623b6074cc8bdbda8bf96f6930a"
562 "platform": "dev",
563 "userid": 1000
564 }
565 }
566 The context (a 32-bit unsigned decimal number) can then be used with
568 all later requests.
569 In the case of a hostspec containing authentication information, such
571 as a username, the server will follow the HTTP Basic Authentication
572 protocol to ascertain necessary authentication details from the user,
573 providing the client web application an opportunity to request these
574 from the user.
575 GET /pmapi/metric - pmLookupDesc(3), pmLookupLabels(3), pmLookupName(3),
577 pmLookupText(3)
578 ┌────────────┬────────┬────────────────────────────────────────────────┐
579 │Parameters │ Type │ Explanation │
580 ├────────────┼────────┼────────────────────────────────────────────────┤
581 │name │ string │ An individual metric name │
582 │names │ string │ Comma-separated list of metric names │
583 │pmid │ pmID │ Numeric or pmIDStr(3) metric identifier │
584 │pmids │ string │ Comma-separated numeric or pmIDStr(3) pmIDs │
585 │prefix │ string │ Metric namespace component as in PMNS(5) │
586 ├────────────┼────────┼────────────────────────────────────────────────┤
587 │hostspec │ string │ Host specification as described in PCPIntro(1) │
588 │context │ number │ Web context number (optional like hostspec) │
589 │polltimeout │ number │ Seconds of inactivity before context closed │
590 │client │ string │ Request identifier sent back with response │
591 └────────────┴────────┴────────────────────────────────────────────────┘
592 The metric endpoint provides detailed PMAPI metric metadata for one or
593 more metrics. If no parameters are supplied, the response will be for
594 all metrics found when traversing the entire Performance Metrics Name
595 Space (PMNS).
596 The prefix parameter can be used to specify a subtree of the PMNS for
598 traversal. Alternatively, a specific metric or comma-separated list of
599 metrics can be specified using either name or names
600 The server response is a JSON document that provides metric metadata as
602 an array.
603 $ curl -s http://localhost:44322/pmapi/metric?names=kernel.all.load,disk.all.read | pmjson
605 {
606 "context": 348734,
607 "metrics": [
608 {
609 "name": "kernel.all.load",
610 "pmid": "60.2.0",
611 "indom": "60.2",
612 "type": "FLOAT",
613 "sem": "instant",
614 "units": "none",
615 "series": "d2b28c7f6dc0d69ffd21dba7ba955e78c37719b",
616 "source": "05af7f3eb840277fd3cfa91f90ef0067199743c",
617 "labels": {
618 "agent": "linux",
619 "domainname": "acme.com",
620 "groupid": 1000,
621 "hostname": "www.acme.com",
622 "platform": "dev",
623 "userid": 1000
624 },
625 "text-oneline": "1, 5 and 15 minute load average"
626 },
627 {
628 "name": "disk.all.read",
629 "pmid": "60.0.24",
630 "type": "U64",
631 "sem": "counter",
632 "units": "count",
633 "series": "d2b28c7f6dc0d69ffd21dba7ba955e78c37719b",
634 "source": "05af7f3eb840277fd3cfa91f90ef0067199743c",
635 "labels": {
636 "agent": "linux",
637 "domainname": "acme.com",
638 "groupid": 1000,
639 "hostname": "www.acme.com",
640 "platform": "dev",
641 "userid": 1000
642 },
643 "text-oneline": "total read operations, summed for all disks",
644 "text-help": "Cumulative number of disk read operations [...]"
645 }
646 ]
647 }
648 Most of the fields are directly transcribed from the PMAPI calls for
649 metric descriptors, labels and help text mentioned above and are exact‐
650 ly as would be observed using the pminfo(1) command with the -dlmstT
651 options.
652 The semantics, type and units fields are as returned by pmTypeStr(3),
654 pmUnitsStr(3) and pmSemStr(3).
655 GET /pmapi/fetch - pmFetch(3)
657 ┌────────────┬────────┬────────────────────────────────────────────────┐
658 │Parameters │ Type │ Explanation │
659 ├────────────┼────────┼────────────────────────────────────────────────┤
660 │delta │ string │ Sampling interval in pmParseInterval(3) form │
661 │name │ string │ An individual metric name │
662 │names │ string │ Comma-separated list of metric names │
663 │pmid │ pmID │ Numeric or pmIDStr(3) metric identifier │
664 │pmids │ string │ Comma-separated numeric or pmIDStr(3) pmIDs │
665 ├────────────┼────────┼────────────────────────────────────────────────┤
666 │hostspec │ string │ Host specification as described in PCPIntro(1) │
667 │context │ number │ Web context number (optional like hostspec) │
668 │polltimeout │ number │ Seconds of inactivity before context closed │
669 │client │ string │ Request identifier sent back with response │
670 └────────────┴────────┴────────────────────────────────────────────────┘
671 This request fetches (samples) current values for given metrics.
672 If any of the names or pmids provided are valid, the response is a JSON
674 document that provides the values for all instances of the metrics, un‐
675 less a instance profile has been set for the web context (see section
676 on InDom profiles below).
677 $ curl -s http://localhost:44322/pmapi/fetch?names=kernel.all.load,disk.all.read | pmjson
679 {
680 "context": 348734,
681 "timestamp": 1547483646.2147431,
682 "values": [
683 {
684 "pmid": "60.2.0",
685 "name": "kernel.all.load",
686 "instances:" [
687 { "instance": 1, "value": 0.1 },
688 { "instance": 5, "value": 0.17 },
689 { "instance": 15, "value": 0.22 }
690 ]
691 },
692 {
693 "pmid":"60.0.24",
694 "name":"disk.all.read",
695 "instances:" [
696 { "instance": null, "value": 639231 }
697 ]
698 }
699 ]
700 }
701 The response fields map directly to fields from the underlying pm‐
702 Fetch(3) sampling interface.
703 Numeric metric types are represented as JSON integer or floating-point
705 values. Strings are passed verbatim, except that non-ASCII values are
706 replaced with a Unicode 0xFFFD replacement character code.
707 In backward compatibility mode the timestamp is presented as a JSON map
709 with second (sec) and microsecond (us) fields, instead of using the
710 more compact floating point representation shown above.
711 GET /pmapi/children - pmGetChildren(3), pmGetChildrenStatus(3)
713 ┌────────────┬────────┬────────────────────────────────────────────────┐
714 │Parameters │ Type │ Explanation │
715 ├────────────┼────────┼────────────────────────────────────────────────┤
716 │prefix │ string │ Metric namespace component as in PMNS(5) │
717 ├────────────┼────────┼────────────────────────────────────────────────┤
718 │hostspec │ string │ Host specification as described in PCPIntro(1) │
719 │context │ number │ Web context number (optional like hostspec) │
720 │polltimeout │ number │ Seconds of inactivity before context closed │
721 │client │ string │ Request identifier sent back with response │
722 └────────────┴────────┴────────────────────────────────────────────────┘
723 The children endpoint provides iterative namespace traversal for a con‐
724 text. If no parameters are supplied, the response will describe the
725 direct descendants of the Performance Metrics Name Space (PMNS) root.
726 The prefix parameter can be used to specify a subtree of the PMNS for
728 traversal.
729 The server response is a JSON document that provides the set of leaf
731 and non-leaf nodes below the given namespace node or root.
732 $ curl -s http://localhost:44322/pmapi/children?prefix=mem | pmjson
734 {
735 "context": 348734,
736 "name": "mem",
737 "leaf": [
738 "physmem",
739 "freemem"
740 ],
741 "nonleaf": [
742 "util",
743 "numa",
744 "vmstat",
745 "buddyinfo",
746 "slabinfo",
747 "zoneinfo",
748 "ksm"
749 ]
750 }
751 GET /pmapi/indom - pmGetInDom(3), pmNameInDom(3), pmLookupInDom(3)
753 ┌────────────┬─────────┬────────────────────────────────────────────────┐
754 │Parameters │ Type │ Explanation │
755 ├────────────┼─────────┼────────────────────────────────────────────────┤
756 │iname │ string │ Comma-separated list of instance names │
757 │indom │ pmInDom │ Numeric or pmInDomStr(3) instance domain │
758 │instance │ number │ Comma-separated list of instance numbers │
759 │match │ string │ Pattern matching style (exact, glob or regex) │
760 │name │ string │ An individual metric name │
761 ├────────────┼─────────┼────────────────────────────────────────────────┤
762 │hostspec │ string │ Host specification as described in PCPIntro(1) │
763 │context │ number │ Web context number (optional like hostspec) │
764 │polltimeout │ number │ Seconds of inactivity before context closed │
765 │client │ string │ Request identifier sent back with response │
766 └────────────┴─────────┴────────────────────────────────────────────────┘
767 This request lists the current instances of an instance domain. The
768 instance domain is either specified directly (in numeric or string
769 form) or indirectly, by association with the specified metric.
770 The request can be further qualified with a comma-separated list of the
772 instances to report on, either by name or number, using the instance
773 and iname parameters.
774 In the case of instance name qualifiers, these will be matched by exact
776 string comparison by default. Alternatively, the match parameter can
777 be used to specify that regular expression or glob pattern matching
778 should be used instead.
779 The response is a JSON document that provides the instance domain meta‐
781 data as an array.
782 $ curl -s http://localhost:44322/pmapi/indom?name=kernel.all.load | pmjson
784 {
785 "context": 348734,
786 "indom": "60.2",
787 "labels": {
788 "domainname": "acme.com",
789 "groupid": 1000,
790 "hostname": "www.acme.com",
791 "machineid": "295b7623b6074cc8bdbda8bf96f6930a"
792 "platform": "dev",
793 "userid": 1000
794 },
795 "instances": [
796 {
797 "instance": 1,
798 "name": "1 minute"
799 "labels": { ... },
800 },
801 {
802 "instance": 5,
803 "name": "5 minute"
804 "labels": { ... },
805 },
806 {
807 "instance": 15,
808 "name": "15 minute"
809 "labels": { ... },
810 }
811 ]
812 }
813 GET /pmapi/profile - pmAddProfile(3), pmDelProfile(3)
815 ┌────────────┬─────────┬────────────────────────────────────────────────┐
816 │Parameters │ Type │ Explanation │
817 ├────────────┼─────────┼────────────────────────────────────────────────┤
818 │iname │ string │ Comma-separated list of instance names │
819 │indom │ pmInDom │ Numeric or pmInDomStr(3) instance domain │
820 │instance │ number │ Comma-separated list of instance numbers │
821 │expr │ string │ One of "add" or "del" (mandatory). │
822 │match │ string │ Pattern matching style (exact, glob or regex) │
823 ├────────────┼─────────┼────────────────────────────────────────────────┤
824 │hostspec │ string │ Host specification as described in PCPIntro(1) │
825 │context │ number │ Web context number (optional like hostspec) │
826 │polltimeout │ number │ Seconds of inactivity before context closed │
827 │client │ string │ Request identifier sent back with response │
828 └────────────┴─────────┴────────────────────────────────────────────────┘
829 Some PMAPI operations can be performed with an active instance domain
830 profile which restricts (filters) the set of resulting instances re‐
831 turned, as described on pmAddProfile(3).
832 $ curl -s http://localhost:44322/pmapi/profile?expr=add,indom=60.2,iname=1%20minute
834 { "context": 348734, "success": true }
835 GET /pmapi/store - pmStore(3)
837 ┌────────────┬────────┬────────────────────────────────────────────────┐
838 │Parameters │ Type │ Explanation │
839 ├────────────┼────────┼────────────────────────────────────────────────┤
840 │iname │ string │ Comma-separated list of instance names │
841 │instance │ number │ Comma-separated list of instance numbers │
842 │name │ string │ An individual metric name │
843 │value │ (any) │ New value for the given metric instance(s) │
844 ├────────────┼────────┼────────────────────────────────────────────────┤
845 │hostspec │ string │ Host specification as described in PCPIntro(1) │
846 │context │ number │ Web context number (optional like hostspec) │
847 │polltimeout │ number │ Seconds of inactivity before context closed │
848 │client │ string │ Request identifier sent back with response │
849 └────────────┴────────┴────────────────────────────────────────────────┘
850 Some performance metrics allow their value to be modified, for example
851 to re-initialize counters or to modify control variables.
852 This operation takes a single metric name to modify, and optionally
854 specific instances. The mandatory value will be interpreted according
855 to the type of the metric being modified.
856 If successful, the response from these requests is a JSON document of
858 the form:
859 $ curl -s http://localhost:44322/pmapi/store?name=pmcd.control.timeout&value=10
861 {
862 "context": 348734,
863 "success": true
864 }
865 GET /pmapi/derive: pmAddDerived(3)
867 ┌────────────┬────────┬────────────────────────────────────────────────┐
868 │Parameters │ Type │ Explanation │
869 ├────────────┼────────┼────────────────────────────────────────────────┤
870 │expr │ string │ Derived metric expression │
871 │name │ string │ New derived metric name │
872 ├────────────┼────────┼────────────────────────────────────────────────┤
873 │hostspec │ string │ Host specification as described in PCPIntro(1) │
874 │context │ number │ Web context number (optional like hostspec) │
875 │polltimeout │ number │ Seconds of inactivity before context closed │
876 │client │ string │ Request identifier sent back with response │
877 └────────────┴────────┴────────────────────────────────────────────────┘
878 Create a new derived metric, as defined by the pmAddDerived(3) metric
879 interface. Derived metrics are associated with the named context, or a
880 new context is created and returned in the result.
881 This interface is one of the few that allows a POST to be used in place
883 of a GET. In this case the HTTP POST request body may be used to pro‐
884 vide one or more derived metrics specifications (all at once, across
885 multiple lines, as a convenience).
886 $ curl -s http://localhost:44322/pmapi/derive?name=blkio.avgsz&expr=disk.all.blktotal/disk.all.total | pmjson
888 {
889 "context": 348734,
890 "success": true
891 }
892 $ curl -s http://localhost:44322/pmapi/fetch?name=blkio.avgsz&samples=2 | pmjson
894 {
895 "context": 348734,
896 "timestamp": 1547483648.2147428,
897 "values": [
898 {
899 "pmid": "511.0.27",
900 "name": "blkio.avgsz",
901 "instances:" [
902 {
903 "instance": null,
904 "value": 9231
905 }
906 ]
907 }
908 ]
909 }
910 GET /pmapi/metrics: pmLookupDesc(3),pmLookupLabels(3), pmFetch(3)
912 ┌────────────┬─────────┬────────────────────────────────────────────────┐
913 │Parameters │ Type │ Explanation │
914 ├────────────┼─────────┼────────────────────────────────────────────────┤
915 │names │ string │ Comma-separated list of metric names │
916 │times │ boolean │ Append sample times (milliseconds since epoch) │
917 ├────────────┼─────────┼────────────────────────────────────────────────┤
918 │context │ number │ Web context number (optional like hostspec) │
919 │hostspec │ string │ Host specification as described in PCPIntro(1) │
920 │polltimeout │ number │ Seconds of inactivity before context closed │
921 │client │ string │ Request identifier sent back with response │
922 └────────────┴─────────┴────────────────────────────────────────────────┘
923 This request is a subset of the style described in the ``OPEN METRICS''
924 section, allowing a web context identifier to be passed as a parameter.
925 It is otherwise very similar in terms of parameters and response han‐
926 dling, please refer to the earlier section for details.
927
929 For the REST APIs, errors generally result in HTTP-level error respons‐
930 es. Wherever possible, any PMAPI error string will also be provided in
931 a message along with the response.
932 All responses will be returned using HTTP 1.1 protocol and with chunked
934 encoding being used to stream responses that are larger than a config‐
935 ured maximum size. Compression will be used on responses whenever the
936 client indicates appropriate support.
937 An Access-Control-Allow-Origin: * header is added to all REST API re‐
939 sponses.
940
942 PCPIntro(1), curl(1), pmcd(1), pmdaopenmetrics(1), pminfo(1), pmj‐
943 son(1), pmlogger(1), pmproxy(1), pmseries(1), redis-server(1), PCPIn‐
944 tro(3) and PMAPI(3)
945Performance Co-Pilot PCP PMWEBAPI(3)