02f4203ae5b6b39a707627a1b6b61ddde8e25b51
1 /**
2 * collectd - src/memcached.c, based on src/hddtemp.c
3 * Copyright (C) 2007 Antony Dovgal
4 * Copyright (C) 2007-2012 Florian Forster
5 * Copyright (C) 2009 Doug MacEachern
6 * Copyright (C) 2009 Franck Lombardi
7 * Copyright (C) 2012 Nicolas Szalay
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the
11 * Free Software Foundation; either version 2 of the License, or (at your
12 * option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22 *
23 * Authors:
24 * Antony Dovgal <tony at daylessday dot org>
25 * Florian octo Forster <octo at collectd.org>
26 * Doug MacEachern <dougm at hyperic.com>
27 * Franck Lombardi
28 * Nicolas Szalay
29 **/
31 #include "collectd.h"
33 #include "common.h"
34 #include "plugin.h"
35 #include "configfile.h"
37 #include <netdb.h>
38 #include <sys/un.h>
39 #include <netinet/in.h>
40 #include <netinet/tcp.h>
42 #define MEMCACHED_DEF_HOST "127.0.0.1"
43 #define MEMCACHED_DEF_PORT "11211"
45 struct memcached_s
46 {
47 char *name;
48 char *socket;
49 char *host;
50 char *port;
51 };
52 typedef struct memcached_s memcached_t;
54 static _Bool memcached_have_instances = 0;
56 static void memcached_free (void *arg)
57 {
58 memcached_t *st = arg;
59 if (st == NULL)
60 return;
62 sfree (st->name);
63 sfree (st->socket);
64 sfree (st->host);
65 sfree (st->port);
66 sfree (st);
67 }
69 static int memcached_connect_unix (memcached_t *st)
70 {
71 struct sockaddr_un serv_addr = { 0 };
72 int fd;
74 serv_addr.sun_family = AF_UNIX;
75 sstrncpy (serv_addr.sun_path, st->socket,
76 sizeof (serv_addr.sun_path));
78 /* create our socket descriptor */
79 fd = socket (AF_UNIX, SOCK_STREAM, 0);
80 if (fd < 0)
81 {
82 char errbuf[1024];
83 ERROR ("memcached plugin: memcached_connect_unix: socket(2) failed: %s",
84 sstrerror (errno, errbuf, sizeof (errbuf)));
85 return (-1);
86 }
88 /* connect to the memcached daemon */
89 int status = connect (fd, (struct sockaddr *)&serv_addr, sizeof(serv_addr));
90 if (status != 0)
91 {
92 shutdown (fd, SHUT_RDWR);
93 close (fd);
94 fd = -1;
95 }
97 return (fd);
98 } /* int memcached_connect_unix */
100 static int memcached_connect_inet (memcached_t *st)
101 {
102 const char *host;
103 const char *port;
105 struct addrinfo *ai_list, *ai_ptr;
106 int status;
107 int fd = -1;
109 host = (st->host != NULL) ? st->host : MEMCACHED_DEF_HOST;
110 port = (st->port != NULL) ? st->port : MEMCACHED_DEF_PORT;
112 struct addrinfo ai_hints = {
113 .ai_family = AF_UNSPEC,
114 .ai_flags = AI_ADDRCONFIG,
115 .ai_socktype = SOCK_STREAM
116 };
118 status = getaddrinfo (host, port, &ai_hints, &ai_list);
119 if (status != 0)
120 {
121 char errbuf[1024];
122 ERROR ("memcached plugin: memcached_connect_inet: "
123 "getaddrinfo(%s,%s) failed: %s",
124 host, port,
125 (status == EAI_SYSTEM)
126 ? sstrerror (errno, errbuf, sizeof (errbuf))
127 : gai_strerror (status));
128 return (-1);
129 }
131 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
132 {
133 /* create our socket descriptor */
134 fd = socket (ai_ptr->ai_family, ai_ptr->ai_socktype, ai_ptr->ai_protocol);
135 if (fd < 0)
136 {
137 char errbuf[1024];
138 WARNING ("memcached plugin: memcached_connect_inet: "
139 "socket(2) failed: %s",
140 sstrerror (errno, errbuf, sizeof (errbuf)));
141 continue;
142 }
144 /* connect to the memcached daemon */
145 status = (int) connect (fd, ai_ptr->ai_addr, ai_ptr->ai_addrlen);
146 if (status != 0)
147 {
148 shutdown (fd, SHUT_RDWR);
149 close (fd);
150 fd = -1;
151 continue;
152 }
154 /* A socket could be opened and connecting succeeded. We're done. */
155 break;
156 }
158 freeaddrinfo (ai_list);
159 return (fd);
160 } /* int memcached_connect_inet */
162 static int memcached_connect (memcached_t *st)
163 {
164 if (st->socket != NULL)
165 return (memcached_connect_unix (st));
166 else
167 return (memcached_connect_inet (st));
168 }
170 static int memcached_query_daemon (char *buffer, size_t buffer_size, memcached_t *st)
171 {
172 int fd, status;
173 size_t buffer_fill;
175 fd = memcached_connect (st);
176 if (fd < 0) {
177 ERROR ("memcached plugin: Instance \"%s\" could not connect to daemon.",
178 st->name);
179 return -1;
180 }
182 status = (int) swrite (fd, "stats\r\n", strlen ("stats\r\n"));
183 if (status != 0)
184 {
185 char errbuf[1024];
186 ERROR ("memcached plugin: write(2) failed: %s",
187 sstrerror (errno, errbuf, sizeof (errbuf)));
188 shutdown(fd, SHUT_RDWR);
189 close (fd);
190 return (-1);
191 }
193 /* receive data from the memcached daemon */
194 memset (buffer, 0, buffer_size);
196 buffer_fill = 0;
197 while ((status = (int) recv (fd, buffer + buffer_fill,
198 buffer_size - buffer_fill, /* flags = */ 0)) != 0)
199 {
200 char const end_token[5] = {'E', 'N', 'D', '\r', '\n'};
201 if (status < 0)
202 {
203 char errbuf[1024];
205 if ((errno == EAGAIN) || (errno == EINTR))
206 continue;
208 ERROR ("memcached: Error reading from socket: %s",
209 sstrerror (errno, errbuf, sizeof (errbuf)));
210 shutdown(fd, SHUT_RDWR);
211 close (fd);
212 return (-1);
213 }
215 buffer_fill += (size_t) status;
216 if (buffer_fill > buffer_size)
217 {
218 buffer_fill = buffer_size;
219 WARNING ("memcached plugin: Message was truncated.");
220 break;
221 }
223 /* If buffer ends in end_token, we have all the data. */
224 if (memcmp (buffer + buffer_fill - sizeof (end_token),
225 end_token, sizeof (end_token)) == 0)
226 break;
227 } /* while (recv) */
229 status = 0;
230 if (buffer_fill == 0)
231 {
232 WARNING ("memcached plugin: No data returned by memcached.");
233 status = -1;
234 }
236 shutdown(fd, SHUT_RDWR);
237 close(fd);
238 return (status);
239 } /* int memcached_query_daemon */
241 static void memcached_init_vl (value_list_t *vl, memcached_t const *st)
242 {
243 char const *host = st->host;
245 /* Set vl->host to hostname_g, if:
246 * - Legacy mode is used.
247 * - "Socket" option is given (doc: "Host option is ignored").
248 * - "Host" option is not provided.
249 * - "Host" option is set to "localhost" or "127.0.0.1". */
250 if ((strcmp (st->name, "__legacy__") == 0)
251 || (st->socket != NULL)
252 || (st->host == NULL)
253 || (strcmp ("127.0.0.1", st->host) == 0)
254 || (strcmp ("localhost", st->host) == 0))
255 host = hostname_g;
257 sstrncpy (vl->plugin, "memcached", sizeof (vl->plugin));
258 sstrncpy (vl->host, host, sizeof (vl->host));
259 if (strcmp (st->name, "__legacy__") != 0)
260 sstrncpy (vl->plugin_instance, st->name, sizeof (vl->plugin_instance));
261 }
263 static void submit_derive (const char *type, const char *type_inst,
264 derive_t value, memcached_t *st)
265 {
266 value_t values[1];
267 value_list_t vl = VALUE_LIST_INIT;
268 memcached_init_vl (&vl, st);
270 values[0].derive = value;
272 vl.values = values;
273 vl.values_len = 1;
274 sstrncpy (vl.type, type, sizeof (vl.type));
275 if (type_inst != NULL)
276 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
278 plugin_dispatch_values (&vl);
279 }
281 static void submit_derive2 (const char *type, const char *type_inst,
282 derive_t value0, derive_t value1, memcached_t *st)
283 {
284 value_t values[2];
285 value_list_t vl = VALUE_LIST_INIT;
286 memcached_init_vl (&vl, st);
288 values[0].derive = value0;
289 values[1].derive = value1;
291 vl.values = values;
292 vl.values_len = 2;
293 sstrncpy (vl.type, type, sizeof (vl.type));
294 if (type_inst != NULL)
295 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
297 plugin_dispatch_values (&vl);
298 }
300 static void submit_gauge (const char *type, const char *type_inst,
301 gauge_t value, memcached_t *st)
302 {
303 value_t values[1];
304 value_list_t vl = VALUE_LIST_INIT;
305 memcached_init_vl (&vl, st);
307 values[0].gauge = value;
309 vl.values = values;
310 vl.values_len = 1;
311 sstrncpy (vl.type, type, sizeof (vl.type));
312 if (type_inst != NULL)
313 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
315 plugin_dispatch_values (&vl);
316 }
318 static void submit_gauge2 (const char *type, const char *type_inst,
319 gauge_t value0, gauge_t value1, memcached_t *st)
320 {
321 value_t values[2];
322 value_list_t vl = VALUE_LIST_INIT;
323 memcached_init_vl (&vl, st);
325 values[0].gauge = value0;
326 values[1].gauge = value1;
328 vl.values = values;
329 vl.values_len = 2;
330 sstrncpy (vl.type, type, sizeof (vl.type));
331 if (type_inst != NULL)
332 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
334 plugin_dispatch_values (&vl);
335 }
337 static int memcached_read (user_data_t *user_data)
338 {
339 char buf[4096];
340 char *fields[3];
341 char *ptr;
342 char *line;
343 char *saveptr;
344 int fields_num;
346 gauge_t bytes_used = NAN;
347 gauge_t bytes_total = NAN;
348 gauge_t hits = NAN;
349 gauge_t gets = NAN;
350 gauge_t incr_hits = NAN;
351 derive_t incr = 0;
352 gauge_t decr_hits = NAN;
353 derive_t decr = 0;
354 derive_t rusage_user = 0;
355 derive_t rusage_syst = 0;
356 derive_t octets_rx = 0;
357 derive_t octets_tx = 0;
359 memcached_t *st;
360 st = user_data->data;
362 /* get data from daemon */
363 if (memcached_query_daemon (buf, sizeof (buf), st) < 0) {
364 return -1;
365 }
367 #define FIELD_IS(cnst) \
368 (((sizeof(cnst) - 1) == name_len) && (strcmp (cnst, fields[1]) == 0))
370 ptr = buf;
371 saveptr = NULL;
372 while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL)
373 {
374 int name_len;
376 ptr = NULL;
378 fields_num = strsplit(line, fields, 3);
379 if (fields_num != 3)
380 continue;
382 name_len = strlen(fields[1]);
383 if (name_len == 0)
384 continue;
386 /*
387 * For an explanation on these fields please refer to
388 * <https://github.com/memcached/memcached/blob/master/doc/protocol.txt>
389 */
391 /*
392 * CPU time consumed by the memcached process
393 */
394 if (FIELD_IS ("rusage_user"))
395 {
396 rusage_user = atoll (fields[2]);
397 }
398 else if (FIELD_IS ("rusage_system"))
399 {
400 rusage_syst = atoll(fields[2]);
401 }
403 /*
404 * Number of threads of this instance
405 */
406 else if (FIELD_IS ("threads"))
407 {
408 submit_gauge2 ("ps_count", NULL, NAN, atof (fields[2]), st);
409 }
411 /*
412 * Number of items stored
413 */
414 else if (FIELD_IS ("curr_items"))
415 {
416 submit_gauge ("memcached_items", "current", atof (fields[2]), st);
417 }
419 /*
420 * Number of bytes used and available (total - used)
421 */
422 else if (FIELD_IS ("bytes"))
423 {
424 bytes_used = atof (fields[2]);
425 }
426 else if (FIELD_IS ("limit_maxbytes"))
427 {
428 bytes_total = atof(fields[2]);
429 }
431 /*
432 * Connections
433 */
434 else if (FIELD_IS ("curr_connections"))
435 {
436 submit_gauge ("memcached_connections", "current", atof (fields[2]), st);
437 }
438 else if (FIELD_IS ("listen_disabled_num"))
439 {
440 submit_derive ("connections", "listen_disabled", atof (fields[2]), st);
441 }
443 /*
444 * Commands
445 */
446 else if ((name_len > 4) && (strncmp (fields[1], "cmd_", 4) == 0))
447 {
448 const char *name = fields[1] + 4;
449 submit_derive ("memcached_command", name, atoll (fields[2]), st);
450 if (strcmp (name, "get") == 0)
451 gets = atof (fields[2]);
452 }
454 /*
455 * Increment/Decrement
456 */
457 else if (FIELD_IS("incr_misses"))
458 {
459 derive_t incr_count = atoll (fields[2]);
460 submit_derive ("memcached_ops", "incr_misses", incr_count, st);
461 incr += incr_count;
462 }
463 else if (FIELD_IS ("incr_hits"))
464 {
465 derive_t incr_count = atoll (fields[2]);
466 submit_derive ("memcached_ops", "incr_hits", incr_count, st);
467 incr_hits = atof (fields[2]);
468 incr += incr_count;
469 }
470 else if (FIELD_IS ("decr_misses"))
471 {
472 derive_t decr_count = atoll (fields[2]);
473 submit_derive ("memcached_ops", "decr_misses", decr_count, st);
474 decr += decr_count;
475 }
476 else if (FIELD_IS ("decr_hits"))
477 {
478 derive_t decr_count = atoll (fields[2]);
479 submit_derive ("memcached_ops", "decr_hits", decr_count, st);
480 decr_hits = atof (fields[2]);
481 decr += decr_count;
482 }
484 /*
485 * Operations on the cache, i. e. cache hits, cache misses and evictions of items
486 */
487 else if (FIELD_IS ("get_hits"))
488 {
489 submit_derive ("memcached_ops", "hits", atoll (fields[2]), st);
490 hits = atof (fields[2]);
491 }
492 else if (FIELD_IS ("get_misses"))
493 {
494 submit_derive ("memcached_ops", "misses", atoll (fields[2]), st);
495 }
496 else if (FIELD_IS ("evictions"))
497 {
498 submit_derive ("memcached_ops", "evictions", atoll (fields[2]), st);
499 }
501 /*
502 * Network traffic
503 */
504 else if (FIELD_IS ("bytes_read"))
505 {
506 octets_rx = atoll (fields[2]);
507 }
508 else if (FIELD_IS ("bytes_written"))
509 {
510 octets_tx = atoll (fields[2]);
511 }
512 } /* while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL) */
514 if (!isnan (bytes_used) && !isnan (bytes_total) && (bytes_used <= bytes_total))
515 submit_gauge2 ("df", "cache", bytes_used, bytes_total - bytes_used, st);
517 if ((rusage_user != 0) || (rusage_syst != 0))
518 submit_derive2 ("ps_cputime", NULL, rusage_user, rusage_syst, st);
520 if ((octets_rx != 0) || (octets_tx != 0))
521 submit_derive2 ("memcached_octets", NULL, octets_rx, octets_tx, st);
523 if (!isnan (gets) && !isnan (hits))
524 {
525 gauge_t rate = NAN;
527 if (gets != 0.0)
528 rate = 100.0 * hits / gets;
530 submit_gauge ("percent", "hitratio", rate, st);
531 }
533 if (!isnan (incr_hits) && incr != 0)
534 {
535 gauge_t incr_rate = 100.0 * incr_hits / incr;
536 submit_gauge ("percent", "incr_hitratio", incr_rate, st);
537 submit_derive ("memcached_ops", "incr", incr, st);
538 }
540 if (!isnan (decr_hits) && decr != 0)
541 {
542 gauge_t decr_rate = 100.0 * decr_hits / decr;
543 submit_gauge ("percent", "decr_hitratio", decr_rate, st);
544 submit_derive ("memcached_ops", "decr", decr, st);
545 }
547 return 0;
548 } /* int memcached_read */
550 static int memcached_add_read_callback (memcached_t *st)
551 {
552 user_data_t ud = { 0 };
553 char callback_name[3*DATA_MAX_NAME_LEN];
554 int status;
556 ud.data = st;
557 ud.free_func = memcached_free;
559 assert (st->name != NULL);
560 ssnprintf (callback_name, sizeof (callback_name), "memcached/%s", st->name);
562 status = plugin_register_complex_read (/* group = */ "memcached",
563 /* name = */ callback_name,
564 /* callback = */ memcached_read,
565 /* interval = */ 0,
566 /* user_data = */ &ud);
567 return (status);
568 } /* int memcached_add_read_callback */
570 /* Configuration handling functiions
571 * <Plugin memcached>
572 * <Instance "instance_name">
573 * Host foo.zomg.com
574 * Port "1234"
575 * </Instance>
576 * </Plugin>
577 */
578 static int config_add_instance(oconfig_item_t *ci)
579 {
580 memcached_t *st;
581 int i;
582 int status = 0;
584 /* Disable automatic generation of default instance in the init callback. */
585 memcached_have_instances = 1;
587 st = calloc (1, sizeof (*st));
588 if (st == NULL)
589 {
590 ERROR ("memcached plugin: calloc failed.");
591 return (-1);
592 }
594 st->name = NULL;
595 st->socket = NULL;
596 st->host = NULL;
597 st->port = NULL;
599 if (strcasecmp (ci->key, "Plugin") == 0) /* default instance */
600 st->name = sstrdup ("__legacy__");
601 else /* <Instance /> block */
602 status = cf_util_get_string (ci, &st->name);
603 if (status != 0)
604 {
605 sfree (st);
606 return (status);
607 }
608 assert (st->name != NULL);
610 for (i = 0; i < ci->children_num; i++)
611 {
612 oconfig_item_t *child = ci->children + i;
614 if (strcasecmp ("Socket", child->key) == 0)
615 status = cf_util_get_string (child, &st->socket);
616 else if (strcasecmp ("Host", child->key) == 0)
617 status = cf_util_get_string (child, &st->host);
618 else if (strcasecmp ("Port", child->key) == 0)
619 status = cf_util_get_service (child, &st->port);
620 else
621 {
622 WARNING ("memcached plugin: Option `%s' not allowed here.",
623 child->key);
624 status = -1;
625 }
627 if (status != 0)
628 break;
629 }
631 if (status == 0)
632 status = memcached_add_read_callback (st);
634 if (status != 0)
635 {
636 memcached_free(st);
637 return (-1);
638 }
640 return (0);
641 }
643 static int memcached_config (oconfig_item_t *ci)
644 {
645 int status = 0;
646 _Bool have_instance_block = 0;
647 int i;
649 for (i = 0; i < ci->children_num; i++)
650 {
651 oconfig_item_t *child = ci->children + i;
653 if (strcasecmp ("Instance", child->key) == 0)
654 {
655 config_add_instance (child);
656 have_instance_block = 1;
657 }
658 else if (!have_instance_block)
659 {
660 /* Non-instance option: Assume legacy configuration (without <Instance />
661 * blocks) and call config_add_instance() with the <Plugin /> block. */
662 return (config_add_instance (ci));
663 }
664 else
665 WARNING ("memcached plugin: The configuration option "
666 "\"%s\" is not allowed here. Did you "
667 "forget to add an <Instance /> block "
668 "around the configuration?",
669 child->key);
670 } /* for (ci->children) */
672 return (status);
673 }
675 static int memcached_init (void)
676 {
677 memcached_t *st;
678 int status;
680 if (memcached_have_instances)
681 return (0);
683 /* No instances were configured, lets start a default instance. */
684 st = calloc (1, sizeof (*st));
685 if (st == NULL)
686 return (ENOMEM);
687 st->name = sstrdup ("__legacy__");
688 st->socket = NULL;
689 st->host = NULL;
690 st->port = NULL;
692 status = memcached_add_read_callback (st);
693 if (status == 0)
694 memcached_have_instances = 1;
695 else
696 memcached_free (st);
698 return (status);
699 } /* int memcached_init */
701 void module_register (void)
702 {
703 plugin_register_complex_config ("memcached", memcached_config);
704 plugin_register_init ("memcached", memcached_init);
705 }