46155e7e455eea81c5d9e8d69f4ccbb69655bace
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"
32 #include "common.h"
33 #include "plugin.h"
34 #include "configfile.h"
36 #include <netdb.h>
37 #include <sys/un.h>
38 #include <netinet/in.h>
39 #include <netinet/tcp.h>
41 #define MEMCACHED_DEF_HOST "127.0.0.1"
42 #define MEMCACHED_DEF_PORT "11211"
44 struct memcached_s
45 {
46 char *name;
47 char *socket;
48 char *host;
49 char *port;
50 };
51 typedef struct memcached_s memcached_t;
53 static _Bool memcached_have_instances = 0;
55 static void memcached_free (void *arg)
56 {
57 memcached_t *st = arg;
58 if (st == NULL)
59 return;
61 sfree (st->name);
62 sfree (st->socket);
63 sfree (st->host);
64 sfree (st->port);
65 sfree (st);
66 }
68 static int memcached_connect_unix (memcached_t *st)
69 {
70 struct sockaddr_un serv_addr = { 0 };
71 int fd;
73 serv_addr.sun_family = AF_UNIX;
74 sstrncpy (serv_addr.sun_path, st->socket,
75 sizeof (serv_addr.sun_path));
77 /* create our socket descriptor */
78 fd = socket (AF_UNIX, SOCK_STREAM, 0);
79 if (fd < 0)
80 {
81 char errbuf[1024];
82 ERROR ("memcached plugin: memcached_connect_unix: socket(2) failed: %s",
83 sstrerror (errno, errbuf, sizeof (errbuf)));
84 return (-1);
85 }
87 /* connect to the memcached daemon */
88 int status = connect (fd, (struct sockaddr *)&serv_addr, sizeof(serv_addr));
89 if (status != 0)
90 {
91 shutdown (fd, SHUT_RDWR);
92 close (fd);
93 fd = -1;
94 }
96 return (fd);
97 } /* int memcached_connect_unix */
99 static int memcached_connect_inet (memcached_t *st)
100 {
101 const char *host;
102 const char *port;
104 struct addrinfo *ai_list, *ai_ptr;
105 int status;
106 int fd = -1;
108 host = (st->host != NULL) ? st->host : MEMCACHED_DEF_HOST;
109 port = (st->port != NULL) ? st->port : MEMCACHED_DEF_PORT;
111 struct addrinfo ai_hints = {
112 .ai_family = AF_UNSPEC,
113 .ai_flags = AI_ADDRCONFIG,
114 .ai_socktype = SOCK_STREAM
115 };
117 status = getaddrinfo (host, port, &ai_hints, &ai_list);
118 if (status != 0)
119 {
120 char errbuf[1024];
121 ERROR ("memcached plugin: memcached_connect_inet: "
122 "getaddrinfo(%s,%s) failed: %s",
123 host, port,
124 (status == EAI_SYSTEM)
125 ? sstrerror (errno, errbuf, sizeof (errbuf))
126 : gai_strerror (status));
127 return (-1);
128 }
130 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
131 {
132 /* create our socket descriptor */
133 fd = socket (ai_ptr->ai_family, ai_ptr->ai_socktype, ai_ptr->ai_protocol);
134 if (fd < 0)
135 {
136 char errbuf[1024];
137 WARNING ("memcached plugin: memcached_connect_inet: "
138 "socket(2) failed: %s",
139 sstrerror (errno, errbuf, sizeof (errbuf)));
140 continue;
141 }
143 /* connect to the memcached daemon */
144 status = (int) connect (fd, ai_ptr->ai_addr, ai_ptr->ai_addrlen);
145 if (status != 0)
146 {
147 shutdown (fd, SHUT_RDWR);
148 close (fd);
149 fd = -1;
150 continue;
151 }
153 /* A socket could be opened and connecting succeeded. We're done. */
154 break;
155 }
157 freeaddrinfo (ai_list);
158 return (fd);
159 } /* int memcached_connect_inet */
161 static int memcached_connect (memcached_t *st)
162 {
163 if (st->socket != NULL)
164 return (memcached_connect_unix (st));
165 else
166 return (memcached_connect_inet (st));
167 }
169 static int memcached_query_daemon (char *buffer, size_t buffer_size, memcached_t *st)
170 {
171 int fd, status;
172 size_t buffer_fill;
174 fd = memcached_connect (st);
175 if (fd < 0) {
176 ERROR ("memcached plugin: Instance \"%s\" could not connect to daemon.",
177 st->name);
178 return -1;
179 }
181 status = (int) swrite (fd, "stats\r\n", strlen ("stats\r\n"));
182 if (status != 0)
183 {
184 char errbuf[1024];
185 ERROR ("memcached plugin: write(2) failed: %s",
186 sstrerror (errno, errbuf, sizeof (errbuf)));
187 shutdown(fd, SHUT_RDWR);
188 close (fd);
189 return (-1);
190 }
192 /* receive data from the memcached daemon */
193 memset (buffer, 0, buffer_size);
195 buffer_fill = 0;
196 while ((status = (int) recv (fd, buffer + buffer_fill,
197 buffer_size - buffer_fill, /* flags = */ 0)) != 0)
198 {
199 char const end_token[5] = {'E', 'N', 'D', '\r', '\n'};
200 if (status < 0)
201 {
202 char errbuf[1024];
204 if ((errno == EAGAIN) || (errno == EINTR))
205 continue;
207 ERROR ("memcached: Error reading from socket: %s",
208 sstrerror (errno, errbuf, sizeof (errbuf)));
209 shutdown(fd, SHUT_RDWR);
210 close (fd);
211 return (-1);
212 }
214 buffer_fill += (size_t) status;
215 if (buffer_fill > buffer_size)
216 {
217 buffer_fill = buffer_size;
218 WARNING ("memcached plugin: Message was truncated.");
219 break;
220 }
222 /* If buffer ends in end_token, we have all the data. */
223 if (memcmp (buffer + buffer_fill - sizeof (end_token),
224 end_token, sizeof (end_token)) == 0)
225 break;
226 } /* while (recv) */
228 status = 0;
229 if (buffer_fill == 0)
230 {
231 WARNING ("memcached plugin: No data returned by memcached.");
232 status = -1;
233 }
235 shutdown(fd, SHUT_RDWR);
236 close(fd);
237 return (status);
238 } /* int memcached_query_daemon */
240 static void memcached_init_vl (value_list_t *vl, memcached_t const *st)
241 {
242 sstrncpy (vl->plugin, "memcached", sizeof (vl->plugin));
243 if (strcmp (st->name, "__legacy__") == 0) /* legacy mode */
244 {
245 sstrncpy (vl->host, hostname_g, sizeof (vl->host));
246 }
247 else
248 {
249 if (st->socket != NULL)
250 sstrncpy (vl->host, hostname_g, sizeof (vl->host));
251 else
252 sstrncpy (vl->host,
253 (st->host != NULL) ? st->host : MEMCACHED_DEF_HOST,
254 sizeof (vl->host));
255 sstrncpy (vl->plugin_instance, st->name, sizeof (vl->plugin_instance));
256 }
257 }
259 static void submit_derive (const char *type, const char *type_inst,
260 derive_t value, memcached_t *st)
261 {
262 value_t values[1];
263 value_list_t vl = VALUE_LIST_INIT;
264 memcached_init_vl (&vl, st);
266 values[0].derive = value;
268 vl.values = values;
269 vl.values_len = 1;
270 sstrncpy (vl.type, type, sizeof (vl.type));
271 if (type_inst != NULL)
272 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
274 plugin_dispatch_values (&vl);
275 }
277 static void submit_derive2 (const char *type, const char *type_inst,
278 derive_t value0, derive_t value1, memcached_t *st)
279 {
280 value_t values[2];
281 value_list_t vl = VALUE_LIST_INIT;
282 memcached_init_vl (&vl, st);
284 values[0].derive = value0;
285 values[1].derive = value1;
287 vl.values = values;
288 vl.values_len = 2;
289 sstrncpy (vl.type, type, sizeof (vl.type));
290 if (type_inst != NULL)
291 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
293 plugin_dispatch_values (&vl);
294 }
296 static void submit_gauge (const char *type, const char *type_inst,
297 gauge_t value, memcached_t *st)
298 {
299 value_t values[1];
300 value_list_t vl = VALUE_LIST_INIT;
301 memcached_init_vl (&vl, st);
303 values[0].gauge = value;
305 vl.values = values;
306 vl.values_len = 1;
307 sstrncpy (vl.type, type, sizeof (vl.type));
308 if (type_inst != NULL)
309 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
311 plugin_dispatch_values (&vl);
312 }
314 static void submit_gauge2 (const char *type, const char *type_inst,
315 gauge_t value0, gauge_t value1, memcached_t *st)
316 {
317 value_t values[2];
318 value_list_t vl = VALUE_LIST_INIT;
319 memcached_init_vl (&vl, st);
321 values[0].gauge = value0;
322 values[1].gauge = value1;
324 vl.values = values;
325 vl.values_len = 2;
326 sstrncpy (vl.type, type, sizeof (vl.type));
327 if (type_inst != NULL)
328 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
330 plugin_dispatch_values (&vl);
331 }
333 static int memcached_read (user_data_t *user_data)
334 {
335 char buf[4096];
336 char *fields[3];
337 char *ptr;
338 char *line;
339 char *saveptr;
340 int fields_num;
342 gauge_t bytes_used = NAN;
343 gauge_t bytes_total = NAN;
344 gauge_t hits = NAN;
345 gauge_t gets = NAN;
346 gauge_t incr_hits = NAN;
347 derive_t incr = 0;
348 gauge_t decr_hits = NAN;
349 derive_t decr = 0;
350 derive_t rusage_user = 0;
351 derive_t rusage_syst = 0;
352 derive_t octets_rx = 0;
353 derive_t octets_tx = 0;
355 memcached_t *st;
356 st = user_data->data;
358 /* get data from daemon */
359 if (memcached_query_daemon (buf, sizeof (buf), st) < 0) {
360 return -1;
361 }
363 #define FIELD_IS(cnst) \
364 (((sizeof(cnst) - 1) == name_len) && (strcmp (cnst, fields[1]) == 0))
366 ptr = buf;
367 saveptr = NULL;
368 while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL)
369 {
370 int name_len;
372 ptr = NULL;
374 fields_num = strsplit(line, fields, 3);
375 if (fields_num != 3)
376 continue;
378 name_len = strlen(fields[1]);
379 if (name_len == 0)
380 continue;
382 /*
383 * For an explanation on these fields please refer to
384 * <https://github.com/memcached/memcached/blob/master/doc/protocol.txt>
385 */
387 /*
388 * CPU time consumed by the memcached process
389 */
390 if (FIELD_IS ("rusage_user"))
391 {
392 rusage_user = atoll (fields[2]);
393 }
394 else if (FIELD_IS ("rusage_system"))
395 {
396 rusage_syst = atoll(fields[2]);
397 }
399 /*
400 * Number of threads of this instance
401 */
402 else if (FIELD_IS ("threads"))
403 {
404 submit_gauge2 ("ps_count", NULL, NAN, atof (fields[2]), st);
405 }
407 /*
408 * Number of items stored
409 */
410 else if (FIELD_IS ("curr_items"))
411 {
412 submit_gauge ("memcached_items", "current", atof (fields[2]), st);
413 }
415 /*
416 * Number of bytes used and available (total - used)
417 */
418 else if (FIELD_IS ("bytes"))
419 {
420 bytes_used = atof (fields[2]);
421 }
422 else if (FIELD_IS ("limit_maxbytes"))
423 {
424 bytes_total = atof(fields[2]);
425 }
427 /*
428 * Connections
429 */
430 else if (FIELD_IS ("curr_connections"))
431 {
432 submit_gauge ("memcached_connections", "current", atof (fields[2]), st);
433 }
434 else if (FIELD_IS ("listen_disabled_num"))
435 {
436 submit_derive ("connections", "listen_disabled", atof (fields[2]), st);
437 }
439 /*
440 * Commands
441 */
442 else if ((name_len > 4) && (strncmp (fields[1], "cmd_", 4) == 0))
443 {
444 const char *name = fields[1] + 4;
445 submit_derive ("memcached_command", name, atoll (fields[2]), st);
446 if (strcmp (name, "get") == 0)
447 gets = atof (fields[2]);
448 }
450 /*
451 * Increment/Decrement
452 */
453 else if (FIELD_IS("incr_misses"))
454 {
455 derive_t incr_count = atoll (fields[2]);
456 submit_derive ("memcached_ops", "incr_misses", incr_count, st);
457 incr += incr_count;
458 }
459 else if (FIELD_IS ("incr_hits"))
460 {
461 derive_t incr_count = atoll (fields[2]);
462 submit_derive ("memcached_ops", "incr_hits", incr_count, st);
463 incr_hits = atof (fields[2]);
464 incr += incr_count;
465 }
466 else if (FIELD_IS ("decr_misses"))
467 {
468 derive_t decr_count = atoll (fields[2]);
469 submit_derive ("memcached_ops", "decr_misses", decr_count, st);
470 decr += decr_count;
471 }
472 else if (FIELD_IS ("decr_hits"))
473 {
474 derive_t decr_count = atoll (fields[2]);
475 submit_derive ("memcached_ops", "decr_hits", decr_count, st);
476 decr_hits = atof (fields[2]);
477 decr += decr_count;
478 }
480 /*
481 * Operations on the cache, i. e. cache hits, cache misses and evictions of items
482 */
483 else if (FIELD_IS ("get_hits"))
484 {
485 submit_derive ("memcached_ops", "hits", atoll (fields[2]), st);
486 hits = atof (fields[2]);
487 }
488 else if (FIELD_IS ("get_misses"))
489 {
490 submit_derive ("memcached_ops", "misses", atoll (fields[2]), st);
491 }
492 else if (FIELD_IS ("evictions"))
493 {
494 submit_derive ("memcached_ops", "evictions", atoll (fields[2]), st);
495 }
497 /*
498 * Network traffic
499 */
500 else if (FIELD_IS ("bytes_read"))
501 {
502 octets_rx = atoll (fields[2]);
503 }
504 else if (FIELD_IS ("bytes_written"))
505 {
506 octets_tx = atoll (fields[2]);
507 }
508 } /* while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL) */
510 if (!isnan (bytes_used) && !isnan (bytes_total) && (bytes_used <= bytes_total))
511 submit_gauge2 ("df", "cache", bytes_used, bytes_total - bytes_used, st);
513 if ((rusage_user != 0) || (rusage_syst != 0))
514 submit_derive2 ("ps_cputime", NULL, rusage_user, rusage_syst, st);
516 if ((octets_rx != 0) || (octets_tx != 0))
517 submit_derive2 ("memcached_octets", NULL, octets_rx, octets_tx, st);
519 if (!isnan (gets) && !isnan (hits))
520 {
521 gauge_t rate = NAN;
523 if (gets != 0.0)
524 rate = 100.0 * hits / gets;
526 submit_gauge ("percent", "hitratio", rate, st);
527 }
529 if (!isnan (incr_hits) && incr != 0)
530 {
531 gauge_t incr_rate = 100.0 * incr_hits / incr;
532 submit_gauge ("percent", "incr_hitratio", incr_rate, st);
533 submit_derive ("memcached_ops", "incr", incr, st);
534 }
536 if (!isnan (decr_hits) && decr != 0)
537 {
538 gauge_t decr_rate = 100.0 * decr_hits / decr;
539 submit_gauge ("percent", "decr_hitratio", decr_rate, st);
540 submit_derive ("memcached_ops", "decr", decr, st);
541 }
543 return 0;
544 } /* int memcached_read */
546 static int memcached_add_read_callback (memcached_t *st)
547 {
548 user_data_t ud = { 0 };
549 char callback_name[3*DATA_MAX_NAME_LEN];
550 int status;
552 ud.data = st;
553 ud.free_func = memcached_free;
555 assert (st->name != NULL);
556 ssnprintf (callback_name, sizeof (callback_name), "memcached/%s", st->name);
558 status = plugin_register_complex_read (/* group = */ "memcached",
559 /* name = */ callback_name,
560 /* callback = */ memcached_read,
561 /* interval = */ 0,
562 /* user_data = */ &ud);
563 return (status);
564 } /* int memcached_add_read_callback */
566 /* Configuration handling functiions
567 * <Plugin memcached>
568 * <Instance "instance_name">
569 * Host foo.zomg.com
570 * Port "1234"
571 * </Instance>
572 * </Plugin>
573 */
574 static int config_add_instance(oconfig_item_t *ci)
575 {
576 memcached_t *st;
577 int i;
578 int status = 0;
580 /* Disable automatic generation of default instance in the init callback. */
581 memcached_have_instances = 1;
583 st = calloc (1, sizeof (*st));
584 if (st == NULL)
585 {
586 ERROR ("memcached plugin: calloc failed.");
587 return (-1);
588 }
590 st->name = NULL;
591 st->socket = NULL;
592 st->host = NULL;
593 st->port = NULL;
595 if (strcasecmp (ci->key, "Plugin") == 0) /* default instance */
596 st->name = sstrdup ("__legacy__");
597 else /* <Instance /> block */
598 status = cf_util_get_string (ci, &st->name);
599 if (status != 0)
600 {
601 sfree (st);
602 return (status);
603 }
604 assert (st->name != NULL);
606 for (i = 0; i < ci->children_num; i++)
607 {
608 oconfig_item_t *child = ci->children + i;
610 if (strcasecmp ("Socket", child->key) == 0)
611 status = cf_util_get_string (child, &st->socket);
612 else if (strcasecmp ("Host", child->key) == 0)
613 status = cf_util_get_string (child, &st->host);
614 else if (strcasecmp ("Port", child->key) == 0)
615 status = cf_util_get_service (child, &st->port);
616 else
617 {
618 WARNING ("memcached plugin: Option `%s' not allowed here.",
619 child->key);
620 status = -1;
621 }
623 if (status != 0)
624 break;
625 }
627 if (status == 0)
628 status = memcached_add_read_callback (st);
630 if (status != 0)
631 {
632 memcached_free(st);
633 return (-1);
634 }
636 return (0);
637 }
639 static int memcached_config (oconfig_item_t *ci)
640 {
641 int status = 0;
642 _Bool have_instance_block = 0;
643 int i;
645 for (i = 0; i < ci->children_num; i++)
646 {
647 oconfig_item_t *child = ci->children + i;
649 if (strcasecmp ("Instance", child->key) == 0)
650 {
651 config_add_instance (child);
652 have_instance_block = 1;
653 }
654 else if (!have_instance_block)
655 {
656 /* Non-instance option: Assume legacy configuration (without <Instance />
657 * blocks) and call config_add_instance() with the <Plugin /> block. */
658 return (config_add_instance (ci));
659 }
660 else
661 WARNING ("memcached plugin: The configuration option "
662 "\"%s\" is not allowed here. Did you "
663 "forget to add an <Instance /> block "
664 "around the configuration?",
665 child->key);
666 } /* for (ci->children) */
668 return (status);
669 }
671 static int memcached_init (void)
672 {
673 memcached_t *st;
674 int status;
676 if (memcached_have_instances)
677 return (0);
679 /* No instances were configured, lets start a default instance. */
680 st = calloc (1, sizeof (*st));
681 if (st == NULL)
682 return (ENOMEM);
683 st->name = sstrdup ("__legacy__");
684 st->socket = NULL;
685 st->host = NULL;
686 st->port = NULL;
688 status = memcached_add_read_callback (st);
689 if (status == 0)
690 memcached_have_instances = 1;
691 else
692 memcached_free (st);
694 return (status);
695 } /* int memcached_init */
697 void module_register (void)
698 {
699 plugin_register_complex_config ("memcached", memcached_config);
700 plugin_register_init ("memcached", memcached_init);
701 }