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
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.
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.
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
24 * Antony Dovgal <tony at daylessday dot org>
25 * Florian octo Forster <octo at collectd.org>
26 * Doug MacEachern <dougm at hyperic.com>
35 #include "configfile.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"
52 typedef struct memcached_s memcached_t;
54 static _Bool memcached_have_instances = 0;
56 static void memcached_free (void *arg)
58 memcached_t *st = arg;
69 static int memcached_connect_unix (memcached_t *st)
71 struct sockaddr_un serv_addr = { 0 };
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);
83 ERROR ("memcached plugin: memcached_connect_unix: socket(2) failed: %s",
84 sstrerror (errno, errbuf, sizeof (errbuf)));
88 /* connect to the memcached daemon */
89 int status = connect (fd, (struct sockaddr *)&serv_addr, sizeof(serv_addr));
92 shutdown (fd, SHUT_RDWR);
98 } /* int memcached_connect_unix */
100 static int memcached_connect_inet (memcached_t *st)
105 struct addrinfo *ai_list;
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
118 status = getaddrinfo (host, port, &ai_hints, &ai_list);
122 ERROR ("memcached plugin: memcached_connect_inet: "
123 "getaddrinfo(%s,%s) failed: %s",
125 (status == EAI_SYSTEM)
126 ? sstrerror (errno, errbuf, sizeof (errbuf))
127 : gai_strerror (status));
131 for (struct addrinfo *ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
133 /* create our socket descriptor */
134 fd = socket (ai_ptr->ai_family, ai_ptr->ai_socktype, ai_ptr->ai_protocol);
138 WARNING ("memcached plugin: memcached_connect_inet: "
139 "socket(2) failed: %s",
140 sstrerror (errno, errbuf, sizeof (errbuf)));
144 /* connect to the memcached daemon */
145 status = (int) connect (fd, ai_ptr->ai_addr, ai_ptr->ai_addrlen);
148 shutdown (fd, SHUT_RDWR);
154 /* A socket could be opened and connecting succeeded. We're done. */
158 freeaddrinfo (ai_list);
160 } /* int memcached_connect_inet */
162 static int memcached_connect (memcached_t *st)
164 if (st->socket != NULL)
165 return (memcached_connect_unix (st));
167 return (memcached_connect_inet (st));
170 static int memcached_query_daemon (char *buffer, size_t buffer_size, memcached_t *st)
175 fd = memcached_connect (st);
177 ERROR ("memcached plugin: Instance \"%s\" could not connect to daemon.",
182 status = (int) swrite (fd, "stats\r\n", strlen ("stats\r\n"));
186 ERROR ("memcached plugin: write(2) failed: %s",
187 sstrerror (errno, errbuf, sizeof (errbuf)));
188 shutdown(fd, SHUT_RDWR);
193 /* receive data from the memcached daemon */
194 memset (buffer, 0, buffer_size);
197 while ((status = (int) recv (fd, buffer + buffer_fill,
198 buffer_size - buffer_fill, /* flags = */ 0)) != 0)
200 char const end_token[5] = {'E', 'N', 'D', '\r', '\n'};
205 if ((errno == EAGAIN) || (errno == EINTR))
208 ERROR ("memcached: Error reading from socket: %s",
209 sstrerror (errno, errbuf, sizeof (errbuf)));
210 shutdown(fd, SHUT_RDWR);
215 buffer_fill += (size_t) status;
216 if (buffer_fill > buffer_size)
218 buffer_fill = buffer_size;
219 WARNING ("memcached plugin: Message was truncated.");
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)
230 if (buffer_fill == 0)
232 WARNING ("memcached plugin: No data returned by memcached.");
236 shutdown(fd, SHUT_RDWR);
239 } /* int memcached_query_daemon */
241 static void memcached_init_vl (value_list_t *vl, memcached_t const *st)
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))
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));
263 static void submit_derive (const char *type, const char *type_inst,
264 derive_t value, memcached_t *st)
267 value_list_t vl = VALUE_LIST_INIT;
268 memcached_init_vl (&vl, st);
270 values[0].derive = value;
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);
281 static void submit_derive2 (const char *type, const char *type_inst,
282 derive_t value0, derive_t value1, memcached_t *st)
285 value_list_t vl = VALUE_LIST_INIT;
286 memcached_init_vl (&vl, st);
288 values[0].derive = value0;
289 values[1].derive = value1;
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);
300 static void submit_gauge (const char *type, const char *type_inst,
301 gauge_t value, memcached_t *st)
304 value_list_t vl = VALUE_LIST_INIT;
305 memcached_init_vl (&vl, st);
307 values[0].gauge = value;
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);
318 static void submit_gauge2 (const char *type, const char *type_inst,
319 gauge_t value0, gauge_t value1, memcached_t *st)
322 value_list_t vl = VALUE_LIST_INIT;
323 memcached_init_vl (&vl, st);
325 values[0].gauge = value0;
326 values[1].gauge = value1;
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);
337 static int memcached_read (user_data_t *user_data)
346 gauge_t bytes_used = NAN;
347 gauge_t bytes_total = NAN;
350 gauge_t incr_hits = NAN;
352 gauge_t decr_hits = NAN;
354 derive_t rusage_user = 0;
355 derive_t rusage_syst = 0;
356 derive_t octets_rx = 0;
357 derive_t octets_tx = 0;
360 st = user_data->data;
362 /* get data from daemon */
363 if (memcached_query_daemon (buf, sizeof (buf), st) < 0) {
367 #define FIELD_IS(cnst) \
368 (((sizeof(cnst) - 1) == name_len) && (strcmp (cnst, fields[1]) == 0))
372 while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL)
378 fields_num = strsplit(line, fields, 3);
382 name_len = strlen(fields[1]);
387 * For an explanation on these fields please refer to
388 * <https://github.com/memcached/memcached/blob/master/doc/protocol.txt>
392 * CPU time consumed by the memcached process
394 if (FIELD_IS ("rusage_user"))
396 rusage_user = atoll (fields[2]);
398 else if (FIELD_IS ("rusage_system"))
400 rusage_syst = atoll(fields[2]);
404 * Number of threads of this instance
406 else if (FIELD_IS ("threads"))
408 submit_gauge2 ("ps_count", NULL, NAN, atof (fields[2]), st);
412 * Number of items stored
414 else if (FIELD_IS ("curr_items"))
416 submit_gauge ("memcached_items", "current", atof (fields[2]), st);
420 * Number of bytes used and available (total - used)
422 else if (FIELD_IS ("bytes"))
424 bytes_used = atof (fields[2]);
426 else if (FIELD_IS ("limit_maxbytes"))
428 bytes_total = atof(fields[2]);
434 else if (FIELD_IS ("curr_connections"))
436 submit_gauge ("memcached_connections", "current", atof (fields[2]), st);
438 else if (FIELD_IS ("listen_disabled_num"))
440 submit_derive ("connections", "listen_disabled", atof (fields[2]), st);
446 else if ((name_len > 4) && (strncmp (fields[1], "cmd_", 4) == 0))
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]);
455 * Increment/Decrement
457 else if (FIELD_IS("incr_misses"))
459 derive_t incr_count = atoll (fields[2]);
460 submit_derive ("memcached_ops", "incr_misses", incr_count, st);
463 else if (FIELD_IS ("incr_hits"))
465 derive_t incr_count = atoll (fields[2]);
466 submit_derive ("memcached_ops", "incr_hits", incr_count, st);
467 incr_hits = atof (fields[2]);
470 else if (FIELD_IS ("decr_misses"))
472 derive_t decr_count = atoll (fields[2]);
473 submit_derive ("memcached_ops", "decr_misses", decr_count, st);
476 else if (FIELD_IS ("decr_hits"))
478 derive_t decr_count = atoll (fields[2]);
479 submit_derive ("memcached_ops", "decr_hits", decr_count, st);
480 decr_hits = atof (fields[2]);
485 * Operations on the cache, i. e. cache hits, cache misses and evictions of items
487 else if (FIELD_IS ("get_hits"))
489 submit_derive ("memcached_ops", "hits", atoll (fields[2]), st);
490 hits = atof (fields[2]);
492 else if (FIELD_IS ("get_misses"))
494 submit_derive ("memcached_ops", "misses", atoll (fields[2]), st);
496 else if (FIELD_IS ("evictions"))
498 submit_derive ("memcached_ops", "evictions", atoll (fields[2]), st);
504 else if (FIELD_IS ("bytes_read"))
506 octets_rx = atoll (fields[2]);
508 else if (FIELD_IS ("bytes_written"))
510 octets_tx = atoll (fields[2]);
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))
528 rate = 100.0 * hits / gets;
530 submit_gauge ("percent", "hitratio", rate, st);
533 if (!isnan (incr_hits) && incr != 0)
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);
540 if (!isnan (decr_hits) && decr != 0)
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);
548 } /* int memcached_read */
550 static int memcached_add_read_callback (memcached_t *st)
552 user_data_t ud = { 0 };
553 char callback_name[3*DATA_MAX_NAME_LEN];
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,
566 /* user_data = */ &ud);
568 } /* int memcached_add_read_callback */
570 /* Configuration handling functiions
572 * <Instance "instance_name">
578 static int config_add_instance(oconfig_item_t *ci)
583 /* Disable automatic generation of default instance in the init callback. */
584 memcached_have_instances = 1;
586 st = calloc (1, sizeof (*st));
589 ERROR ("memcached plugin: calloc failed.");
598 if (strcasecmp (ci->key, "Plugin") == 0) /* default instance */
599 st->name = sstrdup ("__legacy__");
600 else /* <Instance /> block */
601 status = cf_util_get_string (ci, &st->name);
607 assert (st->name != NULL);
609 for (int i = 0; i < ci->children_num; i++)
611 oconfig_item_t *child = ci->children + i;
613 if (strcasecmp ("Socket", child->key) == 0)
614 status = cf_util_get_string (child, &st->socket);
615 else if (strcasecmp ("Host", child->key) == 0)
616 status = cf_util_get_string (child, &st->host);
617 else if (strcasecmp ("Port", child->key) == 0)
618 status = cf_util_get_service (child, &st->port);
621 WARNING ("memcached plugin: Option `%s' not allowed here.",
631 status = memcached_add_read_callback (st);
642 static int memcached_config (oconfig_item_t *ci)
645 _Bool have_instance_block = 0;
647 for (int i = 0; i < ci->children_num; i++)
649 oconfig_item_t *child = ci->children + i;
651 if (strcasecmp ("Instance", child->key) == 0)
653 config_add_instance (child);
654 have_instance_block = 1;
656 else if (!have_instance_block)
658 /* Non-instance option: Assume legacy configuration (without <Instance />
659 * blocks) and call config_add_instance() with the <Plugin /> block. */
660 return (config_add_instance (ci));
663 WARNING ("memcached plugin: The configuration option "
664 "\"%s\" is not allowed here. Did you "
665 "forget to add an <Instance /> block "
666 "around the configuration?",
668 } /* for (ci->children) */
673 static int memcached_init (void)
678 if (memcached_have_instances)
681 /* No instances were configured, lets start a default instance. */
682 st = calloc (1, sizeof (*st));
685 st->name = sstrdup ("__legacy__");
690 status = memcached_add_read_callback (st);
692 memcached_have_instances = 1;
697 } /* int memcached_init */
699 void module_register (void)
701 plugin_register_complex_config ("memcached", memcached_config);
702 plugin_register_init ("memcached", memcached_init);