2 * collectd - src/memcached.c, based on src/hddtemp.c
3 * Copyright (C) 2007 Antony Dovgal
4 * Copyright (C) 2007-2010 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>
34 #include "configfile.h"
38 # include <sys/socket.h>
40 # include <netinet/in.h>
41 # include <netinet/tcp.h>
43 /* Hack to work around the missing define in AIX */
45 # define MSG_DONTWAIT MSG_NONBLOCK
48 #define MEMCACHED_DEF_HOST "127.0.0.1"
49 #define MEMCACHED_DEF_PORT "11211"
51 #define MEMCACHED_RETRY_COUNT 100
61 typedef struct memcached_s memcached_t;
63 static int memcached_read (user_data_t *user_data);
65 static void memcached_free (memcached_t *st)
76 static int memcached_query_daemon (char *buffer, int buffer_size, user_data_t *user_data)
85 if (st->socket != NULL) {
86 struct sockaddr_un serv_addr;
88 memset (&serv_addr, 0, sizeof (serv_addr));
89 serv_addr.sun_family = AF_UNIX;
90 sstrncpy (serv_addr.sun_path, st->socket,
91 sizeof (serv_addr.sun_path));
93 /* create our socket descriptor */
94 fd = socket (AF_UNIX, SOCK_STREAM, 0);
97 ERROR ("memcached: unix socket: %s", sstrerror (errno, errbuf,
106 struct addrinfo ai_hints;
107 struct addrinfo *ai_list, *ai_ptr;
110 memset (&ai_hints, '\0', sizeof (ai_hints));
111 ai_hints.ai_flags = 0;
113 ai_hints.ai_flags |= AI_ADDRCONFIG;
115 ai_hints.ai_family = AF_UNSPEC;
116 ai_hints.ai_socktype = SOCK_STREAM;
117 ai_hints.ai_protocol = 0;
119 host = (st->host != NULL) ? st->host : MEMCACHED_DEF_HOST;
120 port = (st->port != NULL) ? st->port : MEMCACHED_DEF_PORT;
122 if ((ai_return = getaddrinfo (host, port, &ai_hints, &ai_list)) != 0) {
124 ERROR ("memcached: getaddrinfo (%s, %s): %s",
126 (ai_return == EAI_SYSTEM)
127 ? sstrerror (errno, errbuf, sizeof (errbuf))
128 : gai_strerror (ai_return));
132 for (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);
137 ERROR ("memcached: socket: %s", sstrerror (errno, errbuf, sizeof (errbuf)));
141 /* connect to the memcached daemon */
142 status = (ssize_t) connect (fd, ai_ptr->ai_addr, ai_ptr->ai_addrlen);
144 shutdown (fd, SHUT_RDWR);
150 /* A socket could be opened and connecting succeeded. We're
155 freeaddrinfo (ai_list);
159 ERROR ("memcached: Could not connect to daemon.");
163 if (send(fd, "stats\r\n", sizeof("stats\r\n") - 1, MSG_DONTWAIT) != (sizeof("stats\r\n") - 1)) {
164 ERROR ("memcached: Could not send command to the memcached daemon.");
172 memset (&p, 0, sizeof (p));
174 p.events = POLLIN | POLLERR | POLLHUP;
177 status = poll (&p, /* nfds = */ 1,
178 /* timeout = */ CDTIME_T_TO_MS (interval_g));
183 ERROR ("memcached: poll(2) timed out after %.3f seconds.",
184 CDTIME_T_TO_DOUBLE (interval_g));
189 ERROR ("memcached: poll(2) failed: %s",
190 sstrerror (errno, errbuf, sizeof (errbuf)));
192 shutdown (fd, SHUT_RDWR);
198 /* receive data from the memcached daemon */
199 memset (buffer, '\0', buffer_size);
202 while ((status = recv (fd, buffer + buffer_fill, buffer_size - buffer_fill, MSG_DONTWAIT)) != 0) {
203 if (i > MEMCACHED_RETRY_COUNT) {
204 ERROR("recv() timed out");
212 if (errno == EAGAIN) {
216 ERROR ("memcached: Error reading from socket: %s",
217 sstrerror (errno, errbuf, sizeof (errbuf)));
218 shutdown(fd, SHUT_RDWR);
222 buffer_fill += status;
224 if (buffer_fill > 3 && buffer[buffer_fill-5] == 'E' && buffer[buffer_fill-4] == 'N' && buffer[buffer_fill-3] == 'D') {
225 /* we got all the data */
230 if (buffer_fill >= buffer_size) {
231 buffer[buffer_size - 1] = '\0';
232 WARNING ("memcached: Message from memcached has been truncated.");
233 } else if (buffer_fill == 0) {
234 WARNING ("memcached: Peer has unexpectedly shut down the socket. "
235 "Buffer: `%s'", buffer);
236 shutdown(fd, SHUT_RDWR);
241 shutdown(fd, SHUT_RDWR);
246 /* Configuration handling functiions
248 * <Instance "instance_name">
254 static int config_add_instance(oconfig_item_t *ci)
260 if ((ci->values_num != 1)
261 || (ci->values[0].type != OCONFIG_TYPE_STRING))
263 WARNING ("memcached plugin: The `%s' config option "
264 "needs exactly one string argument.", ci->key);
268 st = (memcached_t *) malloc (sizeof (*st));
271 ERROR ("memcached plugin: malloc failed.");
279 memset (st, 0, sizeof (*st));
281 status = cf_util_get_string (ci, &st->name);
287 assert (st->name != NULL);
289 for (i = 0; i < ci->children_num; i++)
291 oconfig_item_t *child = ci->children + i;
293 if (strcasecmp ("Socket", child->key) == 0)
294 status = cf_util_get_string (child, &st->socket);
295 else if (strcasecmp ("Host", child->key) == 0)
296 status = cf_util_get_string (child, &st->host);
297 else if (strcasecmp ("Port", child->key) == 0)
298 status = cf_util_get_service (child, &st->port);
301 WARNING ("memcached plugin: Option `%s' not allowed here.",
313 char callback_name[3*DATA_MAX_NAME_LEN];
315 memset (&ud, 0, sizeof (ud));
317 ud.free_func = (void *) memcached_free;
319 memset (callback_name, 0, sizeof (callback_name));
320 ssnprintf (callback_name, sizeof (callback_name),
322 (st->host != NULL) ? st->host : MEMCACHED_DEF_HOST,
323 (st->port != NULL) ? st->port : MEMCACHED_DEF_PORT)
325 status = plugin_register_complex_read (/* group = */ "memcached",
326 /* name = */ callback_name,
327 /* callback = */ memcached_read,
328 /* interval = */ NULL,
329 /* user_data = */ &ud);
341 static int memcached_config (oconfig_item_t *ci)
346 for (i = 0; i < ci->children_num; i++)
348 oconfig_item_t *child = ci->children + i;
350 if (strcasecmp ("Instance", child->key) == 0)
351 config_add_instance (child);
353 WARNING ("memcached plugin: The configuration option "
354 "\"%s\" is not allowed here. Did you "
355 "forget to add an <Instance /> block "
356 "around the configuration?",
358 } /* for (ci->children) */
363 static void submit_derive (const char *type, const char *type_inst,
364 derive_t value, memcached_t *st)
367 value_list_t vl = VALUE_LIST_INIT;
369 values[0].derive = value;
373 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
374 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
375 if (st->name != NULL)
376 sstrncpy (vl.plugin_instance, st->name, sizeof (vl.plugin_instance));
377 sstrncpy (vl.type, type, sizeof (vl.type));
378 if (type_inst != NULL)
379 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
381 plugin_dispatch_values (&vl);
384 static void submit_derive2 (const char *type, const char *type_inst,
385 derive_t value0, derive_t value1, memcached_t *st)
388 value_list_t vl = VALUE_LIST_INIT;
390 values[0].derive = value0;
391 values[1].derive = value1;
395 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
396 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
397 if (st->name != NULL)
398 sstrncpy (vl.plugin_instance, st->name, sizeof (vl.plugin_instance));
399 sstrncpy (vl.type, type, sizeof (vl.type));
400 if (type_inst != NULL)
401 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
403 plugin_dispatch_values (&vl);
406 static void submit_gauge (const char *type, const char *type_inst,
407 gauge_t value, memcached_t *st)
410 value_list_t vl = VALUE_LIST_INIT;
412 values[0].gauge = value;
416 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
417 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
418 if (st->name != NULL)
419 sstrncpy (vl.plugin_instance, st->name, sizeof (vl.plugin_instance));
420 sstrncpy (vl.type, type, sizeof (vl.type));
421 if (type_inst != NULL)
422 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
424 plugin_dispatch_values (&vl);
427 static void submit_gauge2 (const char *type, const char *type_inst,
428 gauge_t value0, gauge_t value1, memcached_t *st)
431 value_list_t vl = VALUE_LIST_INIT;
433 values[0].gauge = value0;
434 values[1].gauge = value1;
438 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
439 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
440 if (st->name != NULL)
441 sstrncpy (vl.plugin_instance, st->name, sizeof (vl.plugin_instance));
442 sstrncpy (vl.type, type, sizeof (vl.type));
443 if (type_inst != NULL)
444 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
446 plugin_dispatch_values (&vl);
449 static int memcached_read (user_data_t *user_data)
458 gauge_t bytes_used = NAN;
459 gauge_t bytes_total = NAN;
462 derive_t rusage_user = 0;
463 derive_t rusage_syst = 0;
464 derive_t octets_rx = 0;
465 derive_t octets_tx = 0;
468 st = user_data->data;
470 /* get data from daemon */
471 if (memcached_query_daemon (buf, sizeof (buf), user_data) < 0) {
475 #define FIELD_IS(cnst) \
476 (((sizeof(cnst) - 1) == name_len) && (strcmp (cnst, fields[1]) == 0))
480 while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL)
486 fields_num = strsplit(line, fields, 3);
490 name_len = strlen(fields[1]);
495 * For an explanation on these fields please refer to
496 * <http://code.sixapart.com/svn/memcached/trunk/server/doc/protocol.txt>
500 * CPU time consumed by the memcached process
502 if (FIELD_IS ("rusage_user"))
504 rusage_user = atoll (fields[2]);
506 else if (FIELD_IS ("rusage_system"))
508 rusage_syst = atoll(fields[2]);
512 * Number of threads of this instance
514 else if (FIELD_IS ("threads"))
516 submit_gauge2 ("ps_count", NULL, NAN, atof (fields[2]), st);
520 * Number of items stored
522 else if (FIELD_IS ("curr_items"))
524 submit_gauge ("memcached_items", "current", atof (fields[2]), st);
528 * Number of bytes used and available (total - used)
530 else if (FIELD_IS ("bytes"))
532 bytes_used = atof (fields[2]);
534 else if (FIELD_IS ("limit_maxbytes"))
536 bytes_total = atof(fields[2]);
542 else if (FIELD_IS ("curr_connections"))
544 submit_gauge ("memcached_connections", "current", atof (fields[2]), st);
550 else if ((name_len > 4) && (strncmp (fields[1], "cmd_", 4) == 0))
552 const char *name = fields[1] + 4;
553 submit_derive ("memcached_command", name, atoll (fields[2]), st);
554 if (strcmp (name, "get") == 0)
555 gets = atof (fields[2]);
559 * Operations on the cache, i. e. cache hits, cache misses and evictions of items
561 else if (FIELD_IS ("get_hits"))
563 submit_derive ("memcached_ops", "hits", atoll (fields[2]), st);
564 hits = atof (fields[2]);
566 else if (FIELD_IS ("get_misses"))
568 submit_derive ("memcached_ops", "misses", atoll (fields[2]), st);
570 else if (FIELD_IS ("evictions"))
572 submit_derive ("memcached_ops", "evictions", atoll (fields[2]), st);
578 else if (FIELD_IS ("bytes_read"))
580 octets_rx = atoll (fields[2]);
582 else if (FIELD_IS ("bytes_written"))
584 octets_tx = atoll (fields[2]);
586 } /* while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL) */
588 if (!isnan (bytes_used) && !isnan (bytes_total) && (bytes_used <= bytes_total))
589 submit_gauge2 ("df", "cache", bytes_used, bytes_total - bytes_used, st);
591 if ((rusage_user != 0) || (rusage_syst != 0))
592 submit_derive2 ("ps_cputime", NULL, rusage_user, rusage_syst, st);
594 if ((octets_rx != 0) || (octets_tx != 0))
595 submit_derive2 ("memcached_octets", NULL, octets_rx, octets_tx, st);
597 if (!isnan (gets) && !isnan (hits))
602 rate = 100.0 * hits / gets;
604 submit_gauge ("percent", "hitratio", rate, st);
610 void module_register (void)
612 plugin_register_complex_config ("memcached", memcached_config);