1 /**
2 * collectd - src/memcached.c, based on src/hddtemp.c
3 * Copyright (C) 2007 Antony Dovgal
4 * Copyright (C) 2005,2006 Vincent Stehlé
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; either version 2 of the License, or (at your
9 * option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License along
17 * with this program; if not, write to the Free Software Foundation, Inc.,
18 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 *
20 * Authors:
21 * Antony Dovgal <tony at daylessday dot org>
22 * Vincent Stehlé <vincent.stehle at free.fr>
23 * Florian octo Forster <octo at verplant.org>
24 **/
26 #include "collectd.h"
27 #include "common.h"
28 #include "plugin.h"
29 #include "configfile.h"
31 # include <poll.h>
32 # include <netdb.h>
33 # include <sys/socket.h>
34 # include <netinet/in.h>
35 # include <netinet/tcp.h>
37 #define MEMCACHED_DEF_HOST "127.0.0.1"
38 #define MEMCACHED_DEF_PORT "11211"
40 #define MEMCACHED_RETRY_COUNT 100
42 static const char *config_keys[] =
43 {
44 "Host",
45 "Port"
46 };
47 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
49 static char *memcached_host = NULL;
50 static char memcached_port[16];
52 static int memcached_query_daemon (char *buffer, int buffer_size) /* {{{ */
53 {
54 int fd;
55 ssize_t status;
56 int buffer_fill;
58 const char *host;
59 const char *port;
61 struct addrinfo ai_hints;
62 struct addrinfo *ai_list, *ai_ptr;
63 int ai_return, i = 0;
65 memset (&ai_hints, '\0', sizeof (ai_hints));
66 ai_hints.ai_flags = 0;
67 #ifdef AI_ADDRCONFIG
68 /* ai_hints.ai_flags |= AI_ADDRCONFIG; */
69 #endif
70 ai_hints.ai_family = AF_INET;
71 ai_hints.ai_socktype = SOCK_STREAM;
72 ai_hints.ai_protocol = 0;
74 host = memcached_host;
75 if (host == NULL) {
76 host = MEMCACHED_DEF_HOST;
77 }
79 port = memcached_port;
80 if (strlen (port) == 0) {
81 port = MEMCACHED_DEF_PORT;
82 }
84 if ((ai_return = getaddrinfo (host, port, NULL, &ai_list)) != 0) {
85 char errbuf[1024];
86 ERROR ("memcached: getaddrinfo (%s, %s): %s",
87 host, port,
88 (ai_return == EAI_SYSTEM)
89 ? sstrerror (errno, errbuf, sizeof (errbuf))
90 : gai_strerror (ai_return));
91 return -1;
92 }
94 fd = -1;
95 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next) {
96 /* create our socket descriptor */
97 if ((fd = socket (ai_ptr->ai_family, ai_ptr->ai_socktype, ai_ptr->ai_protocol)) < 0) {
98 char errbuf[1024];
99 ERROR ("memcached: socket: %s", sstrerror (errno, errbuf, sizeof (errbuf)));
100 continue;
101 }
103 /* connect to the memcached daemon */
104 if (connect (fd, (struct sockaddr *) ai_ptr->ai_addr, ai_ptr->ai_addrlen)) {
105 shutdown(fd, SHUT_RDWR);
106 close(fd);
107 fd = -1;
108 continue;
109 }
111 /* A socket could be opened and connecting succeeded. We're
112 * done. */
113 break;
114 }
116 freeaddrinfo (ai_list);
118 if (fd < 0) {
119 ERROR ("memcached: Could not connect to daemon.");
120 return -1;
121 }
123 if (send(fd, "stats\r\n", sizeof("stats\r\n") - 1, MSG_DONTWAIT) != (sizeof("stats\r\n") - 1)) {
124 ERROR ("memcached: Could not send command to the memcached daemon.");
125 return -1;
126 }
128 {
129 struct pollfd p;
130 int status;
132 memset (&p, 0, sizeof (p));
133 p.fd = fd;
134 p.events = POLLIN | POLLERR | POLLHUP;
135 p.revents = 0;
137 status = poll (&p, /* nfds = */ 1, /* timeout = */ 1000 * interval_g);
138 if (status <= 0)
139 {
140 if (status == 0)
141 {
142 ERROR ("memcached: poll(2) timed out after %i seconds.", interval_g);
143 }
144 else
145 {
146 char errbuf[1024];
147 ERROR ("memcached: poll(2) failed: %s",
148 sstrerror (errno, errbuf, sizeof (errbuf)));
149 }
150 shutdown (fd, SHUT_RDWR);
151 close (fd);
152 return (-1);
153 }
154 }
156 /* receive data from the memcached daemon */
157 memset (buffer, '\0', buffer_size);
159 buffer_fill = 0;
160 while ((status = recv (fd, buffer + buffer_fill, buffer_size - buffer_fill, MSG_DONTWAIT)) != 0) {
161 if (i > MEMCACHED_RETRY_COUNT) {
162 ERROR("recv() timed out");
163 break;
164 }
165 i++;
167 if (status == -1) {
168 char errbuf[1024];
170 if (errno == EAGAIN) {
171 continue;
172 }
174 ERROR ("memcached: Error reading from socket: %s",
175 sstrerror (errno, errbuf, sizeof (errbuf)));
176 shutdown(fd, SHUT_RDWR);
177 close (fd);
178 return -1;
179 }
180 buffer_fill += status;
182 if (buffer_fill > 3 && buffer[buffer_fill-5] == 'E' && buffer[buffer_fill-4] == 'N' && buffer[buffer_fill-3] == 'D') {
183 /* we got all the data */
184 break;
185 }
186 }
188 if (buffer_fill >= buffer_size) {
189 buffer[buffer_size - 1] = '\0';
190 WARNING ("memcached: Message from memcached has been truncated.");
191 } else if (buffer_fill == 0) {
192 WARNING ("memcached: Peer has unexpectedly shut down the socket. "
193 "Buffer: `%s'", buffer);
194 shutdown(fd, SHUT_RDWR);
195 close(fd);
196 return -1;
197 }
199 shutdown(fd, SHUT_RDWR);
200 close(fd);
201 return 0;
202 }
203 /* }}} */
205 static int memcached_config (const char *key, const char *value) /* {{{ */
206 {
207 if (strcasecmp (key, "Host") == 0) {
208 if (memcached_host != NULL) {
209 free (memcached_host);
210 }
211 memcached_host = strdup (value);
212 } else if (strcasecmp (key, "Port") == 0) {
213 int port = (int) (atof (value));
214 if ((port > 0) && (port <= 65535)) {
215 ssnprintf (memcached_port, sizeof (memcached_port), "%i", port);
216 } else {
217 sstrncpy (memcached_port, value, sizeof (memcached_port));
218 }
219 } else {
220 return -1;
221 }
223 return 0;
224 }
225 /* }}} */
227 static void submit_counter (const char *type, const char *type_inst,
228 counter_t value) /* {{{ */
229 {
230 value_t values[1];
231 value_list_t vl = VALUE_LIST_INIT;
233 values[0].counter = value;
235 vl.values = values;
236 vl.values_len = 1;
237 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
238 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
239 sstrncpy (vl.type, type, sizeof (vl.type));
240 if (type_inst != NULL)
241 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
243 plugin_dispatch_values (&vl);
244 } /* void memcached_submit_cmd */
245 /* }}} */
247 static void submit_counter2 (const char *type, const char *type_inst,
248 counter_t value0, counter_t value1) /* {{{ */
249 {
250 value_t values[2];
251 value_list_t vl = VALUE_LIST_INIT;
253 values[0].counter = value0;
254 values[1].counter = value1;
256 vl.values = values;
257 vl.values_len = 2;
258 vl.time = time (NULL);
259 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
260 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
261 sstrncpy (vl.type, type, sizeof (vl.type));
262 if (type_inst != NULL)
263 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
265 plugin_dispatch_values (&vl);
266 } /* void memcached_submit_cmd */
267 /* }}} */
269 static void submit_gauge (const char *type, const char *type_inst,
270 gauge_t value) /* {{{ */
271 {
272 value_t values[1];
273 value_list_t vl = VALUE_LIST_INIT;
275 values[0].gauge = value;
277 vl.values = values;
278 vl.values_len = 1;
279 vl.time = time (NULL);
280 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
281 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
282 sstrncpy (vl.type, type, sizeof (vl.type));
283 if (type_inst != NULL)
284 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
286 plugin_dispatch_values (&vl);
287 }
288 /* }}} */
290 static void submit_gauge2 (const char *type, const char *type_inst,
291 gauge_t value0, gauge_t value1) /* {{{ */
292 {
293 value_t values[2];
294 value_list_t vl = VALUE_LIST_INIT;
296 values[0].gauge = value0;
297 values[1].gauge = value1;
299 vl.values = values;
300 vl.values_len = 2;
301 vl.time = time (NULL);
302 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
303 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
304 sstrncpy (vl.type, type, sizeof (vl.type));
305 if (type_inst != NULL)
306 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
308 plugin_dispatch_values (&vl);
309 }
310 /* }}} */
312 static int memcached_read (void) /* {{{ */
313 {
314 char buf[1024];
315 char *fields[3];
316 char *ptr;
317 char *line;
318 char *saveptr;
319 int fields_num;
321 gauge_t bytes_used = NAN;
322 gauge_t bytes_total = NAN;
323 gauge_t hits = NAN;
324 gauge_t gets = NAN;
325 counter_t rusage_user = 0;
326 counter_t rusage_syst = 0;
327 counter_t octets_rx = 0;
328 counter_t octets_tx = 0;
330 /* get data from daemon */
331 if (memcached_query_daemon (buf, sizeof (buf)) < 0) {
332 return -1;
333 }
335 #define FIELD_IS(cnst) \
336 (((sizeof(cnst) - 1) == name_len) && (strcmp (cnst, fields[1]) == 0))
338 ptr = buf;
339 saveptr = NULL;
340 while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL)
341 {
342 int name_len;
344 ptr = NULL;
346 fields_num = strsplit(line, fields, 3);
347 if (fields_num != 3)
348 continue;
350 name_len = strlen(fields[1]);
351 if (name_len == 0)
352 continue;
354 /*
355 * For an explanation on these fields please refer to
356 * <http://code.sixapart.com/svn/memcached/trunk/server/doc/protocol.txt>
357 */
359 /*
360 * CPU time consumed by the memcached process
361 */
362 if (FIELD_IS ("rusage_user"))
363 {
364 rusage_user = atoll (fields[2]);
365 }
366 else if (FIELD_IS ("rusage_system"))
367 {
368 rusage_syst = atoll(fields[2]);
369 }
371 /*
372 * Number of threads of this instance
373 */
374 else if (FIELD_IS ("threads"))
375 {
376 submit_gauge2 ("ps_count", NULL, NAN, atof (fields[2]));
377 }
379 /*
380 * Number of items stored
381 */
382 else if (FIELD_IS ("curr_items"))
383 {
384 submit_gauge ("memcached_items", "current", atof (fields[2]));
385 }
386 /*
387 else if (FIELD_IS ("total_items"))
388 {
389 total_items = atoll(fields[2]);
390 }
391 */
393 /*
394 * Number of bytes used and available (total - used)
395 */
396 else if (FIELD_IS ("bytes"))
397 {
398 bytes_used = atof (fields[2]);
399 }
400 else if (FIELD_IS ("limit_maxbytes"))
401 {
402 bytes_total = atof(fields[2]);
403 }
405 /*
406 * Connections
407 */
408 else if (FIELD_IS ("curr_connections"))
409 {
410 submit_gauge ("memcached_connections", "current", atof (fields[2]));
411 }
412 /*
413 else if (FIELD_IS("total_connections"))
414 {
415 total_connections = atoll(fields[2]);
416 }
417 */
419 /*
420 * ``Number of connection structures allocated by the server''
421 else if (FIELD_IS ("connection_structures"))
422 {
423 connection_structures = atof(fields[2]);
424 }
425 */
427 /*
428 * Commands
429 */
430 else if ((name_len > 4) && (strncmp (fields[1], "cmd_", 4) == 0))
431 {
432 const char *name = fields[1] + 4;
433 submit_counter ("memcached_command", name, atoll (fields[2]));
434 if (strcmp (name, "get") == 0)
435 gets = atof (fields[2]);
436 }
438 /*
439 * Operations on the cache, i. e. cache hits, cache misses and evictions of items
440 */
441 else if (FIELD_IS ("get_hits"))
442 {
443 submit_counter ("memcached_ops", "hits", atoll (fields[2]));
444 hits = atof (fields[2]);
445 }
446 else if (FIELD_IS ("get_misses"))
447 {
448 submit_counter ("memcached_ops", "misses", atoll (fields[2]));
449 }
450 else if (FIELD_IS ("evictions"))
451 {
452 submit_counter ("memcached_ops", "evictions", atoll (fields[2]));
453 }
455 /*
456 * Network traffic
457 */
458 else if (FIELD_IS ("bytes_read"))
459 {
460 octets_rx = atoll (fields[2]);
461 }
462 else if (FIELD_IS ("bytes_written"))
463 {
464 octets_tx = atoll (fields[2]);
465 }
466 } /* while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL) */
468 if (!isnan (bytes_used) && !isnan (bytes_total) && (bytes_used <= bytes_total))
469 submit_gauge2 ("df", "cache", bytes_used, bytes_total - bytes_used);
471 if ((rusage_user != 0) || (rusage_syst != 0))
472 submit_counter2 ("ps_cputime", NULL, rusage_user, rusage_syst);
474 if ((octets_rx != 0) || (octets_tx != 0))
475 submit_counter2 ("memcached_octets", NULL, octets_rx, octets_tx);
477 if (!isnan (gets) && !isnan (hits))
478 {
479 gauge_t rate = NAN;
481 if (gets != 0.0)
482 rate = 100.0 * hits / gets;
484 submit_gauge ("percent", "hitratio", rate);
485 }
487 return 0;
488 }
489 /* }}} */
491 void module_register (void) /* {{{ */
492 {
493 plugin_register_config ("memcached", memcached_config, config_keys, config_keys_num);
494 plugin_register_read ("memcached", memcached_read);
495 }
496 /* }}} */
498 /*
499 * Local variables:
500 * tab-width: 4
501 * c-basic-offset: 4
502 * End:
503 * vim600: sw=4 ts=4 fdm=marker
504 * vim<600: sw=4 ts=4
505 */