1 /**
2 * collectd - src/memcached.c, based on src/hddtemp.c
3 * Copyright (C) 2007 Antony Dovgal
4 * Copyright (C) 2007-2009 Florian Forster
5 * Copyright (C) 2009 Doug MacEachern
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or (at your
10 * option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License along
18 * with this program; if not, write to the Free Software Foundation, Inc.,
19 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 *
21 * Authors:
22 * Antony Dovgal <tony at daylessday dot org>
23 * Florian octo Forster <octo at verplant.org>
24 * Doug MacEachern <dougm at hyperic.com>
25 **/
27 #include "collectd.h"
28 #include "common.h"
29 #include "plugin.h"
30 #include "configfile.h"
32 # include <poll.h>
33 # include <netdb.h>
34 # include <sys/socket.h>
35 # include <netinet/in.h>
36 # include <netinet/tcp.h>
38 #define MEMCACHED_DEF_HOST "127.0.0.1"
39 #define MEMCACHED_DEF_PORT "11211"
41 #define MEMCACHED_RETRY_COUNT 100
43 static const char *config_keys[] =
44 {
45 "Host",
46 "Port"
47 };
48 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
50 static char *memcached_host = NULL;
51 static char memcached_port[16];
53 static int memcached_query_daemon (char *buffer, int buffer_size) /* {{{ */
54 {
55 int fd;
56 ssize_t status;
57 int buffer_fill;
59 const char *host;
60 const char *port;
62 struct addrinfo ai_hints;
63 struct addrinfo *ai_list, *ai_ptr;
64 int ai_return, i = 0;
66 memset (&ai_hints, '\0', sizeof (ai_hints));
67 ai_hints.ai_flags = 0;
68 #ifdef AI_ADDRCONFIG
69 /* ai_hints.ai_flags |= AI_ADDRCONFIG; */
70 #endif
71 ai_hints.ai_family = AF_INET;
72 ai_hints.ai_socktype = SOCK_STREAM;
73 ai_hints.ai_protocol = 0;
75 host = memcached_host;
76 if (host == NULL) {
77 host = MEMCACHED_DEF_HOST;
78 }
80 port = memcached_port;
81 if (strlen (port) == 0) {
82 port = MEMCACHED_DEF_PORT;
83 }
85 if ((ai_return = getaddrinfo (host, port, NULL, &ai_list)) != 0) {
86 char errbuf[1024];
87 ERROR ("memcached: getaddrinfo (%s, %s): %s",
88 host, port,
89 (ai_return == EAI_SYSTEM)
90 ? sstrerror (errno, errbuf, sizeof (errbuf))
91 : gai_strerror (ai_return));
92 return -1;
93 }
95 fd = -1;
96 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next) {
97 /* create our socket descriptor */
98 if ((fd = socket (ai_ptr->ai_family, ai_ptr->ai_socktype, ai_ptr->ai_protocol)) < 0) {
99 char errbuf[1024];
100 ERROR ("memcached: socket: %s", sstrerror (errno, errbuf, sizeof (errbuf)));
101 continue;
102 }
104 /* connect to the memcached daemon */
105 if (connect (fd, (struct sockaddr *) ai_ptr->ai_addr, ai_ptr->ai_addrlen)) {
106 shutdown(fd, SHUT_RDWR);
107 close(fd);
108 fd = -1;
109 continue;
110 }
112 /* A socket could be opened and connecting succeeded. We're
113 * done. */
114 break;
115 }
117 freeaddrinfo (ai_list);
119 if (fd < 0) {
120 ERROR ("memcached: Could not connect to daemon.");
121 return -1;
122 }
124 if (send(fd, "stats\r\n", sizeof("stats\r\n") - 1, MSG_DONTWAIT) != (sizeof("stats\r\n") - 1)) {
125 ERROR ("memcached: Could not send command to the memcached daemon.");
126 return -1;
127 }
129 {
130 struct pollfd p;
131 int status;
133 memset (&p, 0, sizeof (p));
134 p.fd = fd;
135 p.events = POLLIN | POLLERR | POLLHUP;
136 p.revents = 0;
138 status = poll (&p, /* nfds = */ 1, /* timeout = */ 1000 * interval_g);
139 if (status <= 0)
140 {
141 if (status == 0)
142 {
143 ERROR ("memcached: poll(2) timed out after %i seconds.", interval_g);
144 }
145 else
146 {
147 char errbuf[1024];
148 ERROR ("memcached: poll(2) failed: %s",
149 sstrerror (errno, errbuf, sizeof (errbuf)));
150 }
151 shutdown (fd, SHUT_RDWR);
152 close (fd);
153 return (-1);
154 }
155 }
157 /* receive data from the memcached daemon */
158 memset (buffer, '\0', buffer_size);
160 buffer_fill = 0;
161 while ((status = recv (fd, buffer + buffer_fill, buffer_size - buffer_fill, MSG_DONTWAIT)) != 0) {
162 if (i > MEMCACHED_RETRY_COUNT) {
163 ERROR("recv() timed out");
164 break;
165 }
166 i++;
168 if (status == -1) {
169 char errbuf[1024];
171 if (errno == EAGAIN) {
172 continue;
173 }
175 ERROR ("memcached: Error reading from socket: %s",
176 sstrerror (errno, errbuf, sizeof (errbuf)));
177 shutdown(fd, SHUT_RDWR);
178 close (fd);
179 return -1;
180 }
181 buffer_fill += status;
183 if (buffer_fill > 3 && buffer[buffer_fill-5] == 'E' && buffer[buffer_fill-4] == 'N' && buffer[buffer_fill-3] == 'D') {
184 /* we got all the data */
185 break;
186 }
187 }
189 if (buffer_fill >= buffer_size) {
190 buffer[buffer_size - 1] = '\0';
191 WARNING ("memcached: Message from memcached has been truncated.");
192 } else if (buffer_fill == 0) {
193 WARNING ("memcached: Peer has unexpectedly shut down the socket. "
194 "Buffer: `%s'", buffer);
195 shutdown(fd, SHUT_RDWR);
196 close(fd);
197 return -1;
198 }
200 shutdown(fd, SHUT_RDWR);
201 close(fd);
202 return 0;
203 }
204 /* }}} */
206 static int memcached_config (const char *key, const char *value) /* {{{ */
207 {
208 if (strcasecmp (key, "Host") == 0) {
209 if (memcached_host != NULL) {
210 free (memcached_host);
211 }
212 memcached_host = strdup (value);
213 } else if (strcasecmp (key, "Port") == 0) {
214 int port = (int) (atof (value));
215 if ((port > 0) && (port <= 65535)) {
216 ssnprintf (memcached_port, sizeof (memcached_port), "%i", port);
217 } else {
218 sstrncpy (memcached_port, value, sizeof (memcached_port));
219 }
220 } else {
221 return -1;
222 }
224 return 0;
225 }
226 /* }}} */
228 static void submit_counter (const char *type, const char *type_inst,
229 counter_t value) /* {{{ */
230 {
231 value_t values[1];
232 value_list_t vl = VALUE_LIST_INIT;
234 values[0].counter = value;
236 vl.values = values;
237 vl.values_len = 1;
238 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
239 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
240 sstrncpy (vl.type, type, sizeof (vl.type));
241 if (type_inst != NULL)
242 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
244 plugin_dispatch_values (&vl);
245 } /* void memcached_submit_cmd */
246 /* }}} */
248 static void submit_counter2 (const char *type, const char *type_inst,
249 counter_t value0, counter_t value1) /* {{{ */
250 {
251 value_t values[2];
252 value_list_t vl = VALUE_LIST_INIT;
254 values[0].counter = value0;
255 values[1].counter = value1;
257 vl.values = values;
258 vl.values_len = 2;
259 vl.time = time (NULL);
260 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
261 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
262 sstrncpy (vl.type, type, sizeof (vl.type));
263 if (type_inst != NULL)
264 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
266 plugin_dispatch_values (&vl);
267 } /* void memcached_submit_cmd */
268 /* }}} */
270 static void submit_gauge (const char *type, const char *type_inst,
271 gauge_t value) /* {{{ */
272 {
273 value_t values[1];
274 value_list_t vl = VALUE_LIST_INIT;
276 values[0].gauge = value;
278 vl.values = values;
279 vl.values_len = 1;
280 vl.time = time (NULL);
281 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
282 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
283 sstrncpy (vl.type, type, sizeof (vl.type));
284 if (type_inst != NULL)
285 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
287 plugin_dispatch_values (&vl);
288 }
289 /* }}} */
291 static void submit_gauge2 (const char *type, const char *type_inst,
292 gauge_t value0, gauge_t value1) /* {{{ */
293 {
294 value_t values[2];
295 value_list_t vl = VALUE_LIST_INIT;
297 values[0].gauge = value0;
298 values[1].gauge = value1;
300 vl.values = values;
301 vl.values_len = 2;
302 vl.time = time (NULL);
303 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
304 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
305 sstrncpy (vl.type, type, sizeof (vl.type));
306 if (type_inst != NULL)
307 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
309 plugin_dispatch_values (&vl);
310 }
311 /* }}} */
313 static int memcached_read (void) /* {{{ */
314 {
315 char buf[1024];
316 char *fields[3];
317 char *ptr;
318 char *line;
319 char *saveptr;
320 int fields_num;
322 gauge_t bytes_used = NAN;
323 gauge_t bytes_total = NAN;
324 gauge_t hits = NAN;
325 gauge_t gets = NAN;
326 counter_t rusage_user = 0;
327 counter_t rusage_syst = 0;
328 counter_t octets_rx = 0;
329 counter_t octets_tx = 0;
331 /* get data from daemon */
332 if (memcached_query_daemon (buf, sizeof (buf)) < 0) {
333 return -1;
334 }
336 #define FIELD_IS(cnst) \
337 (((sizeof(cnst) - 1) == name_len) && (strcmp (cnst, fields[1]) == 0))
339 ptr = buf;
340 saveptr = NULL;
341 while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL)
342 {
343 int name_len;
345 ptr = NULL;
347 fields_num = strsplit(line, fields, 3);
348 if (fields_num != 3)
349 continue;
351 name_len = strlen(fields[1]);
352 if (name_len == 0)
353 continue;
355 /*
356 * For an explanation on these fields please refer to
357 * <http://code.sixapart.com/svn/memcached/trunk/server/doc/protocol.txt>
358 */
360 /*
361 * CPU time consumed by the memcached process
362 */
363 if (FIELD_IS ("rusage_user"))
364 {
365 rusage_user = atoll (fields[2]);
366 }
367 else if (FIELD_IS ("rusage_system"))
368 {
369 rusage_syst = atoll(fields[2]);
370 }
372 /*
373 * Number of threads of this instance
374 */
375 else if (FIELD_IS ("threads"))
376 {
377 submit_gauge2 ("ps_count", NULL, NAN, atof (fields[2]));
378 }
380 /*
381 * Number of items stored
382 */
383 else if (FIELD_IS ("curr_items"))
384 {
385 submit_gauge ("memcached_items", "current", atof (fields[2]));
386 }
387 /*
388 else if (FIELD_IS ("total_items"))
389 {
390 total_items = atoll(fields[2]);
391 }
392 */
394 /*
395 * Number of bytes used and available (total - used)
396 */
397 else if (FIELD_IS ("bytes"))
398 {
399 bytes_used = atof (fields[2]);
400 }
401 else if (FIELD_IS ("limit_maxbytes"))
402 {
403 bytes_total = atof(fields[2]);
404 }
406 /*
407 * Connections
408 */
409 else if (FIELD_IS ("curr_connections"))
410 {
411 submit_gauge ("memcached_connections", "current", atof (fields[2]));
412 }
413 /*
414 else if (FIELD_IS("total_connections"))
415 {
416 total_connections = atoll(fields[2]);
417 }
418 */
420 /*
421 * ``Number of connection structures allocated by the server''
422 else if (FIELD_IS ("connection_structures"))
423 {
424 connection_structures = atof(fields[2]);
425 }
426 */
428 /*
429 * Commands
430 */
431 else if ((name_len > 4) && (strncmp (fields[1], "cmd_", 4) == 0))
432 {
433 const char *name = fields[1] + 4;
434 submit_counter ("memcached_command", name, atoll (fields[2]));
435 if (strcmp (name, "get") == 0)
436 gets = atof (fields[2]);
437 }
439 /*
440 * Operations on the cache, i. e. cache hits, cache misses and evictions of items
441 */
442 else if (FIELD_IS ("get_hits"))
443 {
444 submit_counter ("memcached_ops", "hits", atoll (fields[2]));
445 hits = atof (fields[2]);
446 }
447 else if (FIELD_IS ("get_misses"))
448 {
449 submit_counter ("memcached_ops", "misses", atoll (fields[2]));
450 }
451 else if (FIELD_IS ("evictions"))
452 {
453 submit_counter ("memcached_ops", "evictions", atoll (fields[2]));
454 }
456 /*
457 * Network traffic
458 */
459 else if (FIELD_IS ("bytes_read"))
460 {
461 octets_rx = atoll (fields[2]);
462 }
463 else if (FIELD_IS ("bytes_written"))
464 {
465 octets_tx = atoll (fields[2]);
466 }
467 } /* while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL) */
469 if (!isnan (bytes_used) && !isnan (bytes_total) && (bytes_used <= bytes_total))
470 submit_gauge2 ("df", "cache", bytes_used, bytes_total - bytes_used);
472 if ((rusage_user != 0) || (rusage_syst != 0))
473 submit_counter2 ("ps_cputime", NULL, rusage_user, rusage_syst);
475 if ((octets_rx != 0) || (octets_tx != 0))
476 submit_counter2 ("memcached_octets", NULL, octets_rx, octets_tx);
478 if (!isnan (gets) && !isnan (hits))
479 {
480 gauge_t rate = NAN;
482 if (gets != 0.0)
483 rate = 100.0 * hits / gets;
485 submit_gauge ("percent", "hitratio", rate);
486 }
488 return 0;
489 }
490 /* }}} */
492 void module_register (void) /* {{{ */
493 {
494 plugin_register_config ("memcached", memcached_config, config_keys, config_keys_num);
495 plugin_register_read ("memcached", memcached_read);
496 }
497 /* }}} */
499 /*
500 * Local variables:
501 * tab-width: 4
502 * c-basic-offset: 4
503 * End:
504 * vim600: sw=4 ts=4 fdm=marker
505 * vim<600: sw=4 ts=4
506 */