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 * Copyright (C) 2009 Franck Lombardi
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 *
22 * Authors:
23 * Antony Dovgal <tony at daylessday dot org>
24 * Florian octo Forster <octo at verplant.org>
25 * Doug MacEachern <dougm at hyperic.com>
26 * Franck Lombardi
27 **/
29 #include "collectd.h"
30 #include "common.h"
31 #include "plugin.h"
32 #include "configfile.h"
34 # include <poll.h>
35 # include <netdb.h>
36 # include <sys/socket.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 #define MEMCACHED_RETRY_COUNT 100
46 static const char *config_keys[] =
47 {
48 "Socket",
49 "Host",
50 "Port"
51 };
52 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
54 static char *memcached_socket = NULL;
55 static char *memcached_host = NULL;
56 static char memcached_port[16];
58 static int memcached_query_daemon (char *buffer, int buffer_size) /* {{{ */
59 {
60 int fd;
61 ssize_t status;
62 int buffer_fill;
63 int i = 0;
65 if (memcached_socket != NULL) {
66 struct sockaddr_un serv_addr;
68 memset (&serv_addr, 0, sizeof (serv_addr));
69 serv_addr.sun_family = AF_UNIX;
70 sstrncpy (serv_addr.sun_path, memcached_socket,
71 sizeof (serv_addr.sun_path));
73 /* create our socket descriptor */
74 fd = socket (AF_UNIX, SOCK_STREAM, 0);
75 if (fd < 0) {
76 char errbuf[1024];
77 ERROR ("memcached: unix socket: %s", sstrerror (errno, errbuf,
78 sizeof (errbuf)));
79 return -1;
80 }
82 /* connect to the memcached daemon */
83 status = (ssize_t) connect (fd, (struct sockaddr *) &serv_addr,
84 sizeof (serv_addr));
85 if (status != 0) {
86 shutdown (fd, SHUT_RDWR);
87 close (fd);
88 fd = -1;
89 }
90 }
91 else { /* if (memcached_socket == NULL) */
92 const char *host;
93 const char *port;
95 struct addrinfo ai_hints;
96 struct addrinfo *ai_list, *ai_ptr;
97 int ai_return = 0;
99 memset (&ai_hints, '\0', sizeof (ai_hints));
100 ai_hints.ai_flags = 0;
101 #ifdef AI_ADDRCONFIG
102 /* ai_hints.ai_flags |= AI_ADDRCONFIG; */
103 #endif
104 ai_hints.ai_family = AF_INET;
105 ai_hints.ai_socktype = SOCK_STREAM;
106 ai_hints.ai_protocol = 0;
108 host = memcached_host;
109 if (host == NULL) {
110 host = MEMCACHED_DEF_HOST;
111 }
113 port = memcached_port;
114 if (strlen (port) == 0) {
115 port = MEMCACHED_DEF_PORT;
116 }
118 if ((ai_return = getaddrinfo (host, port, NULL, &ai_list)) != 0) {
119 char errbuf[1024];
120 ERROR ("memcached: getaddrinfo (%s, %s): %s",
121 host, port,
122 (ai_return == EAI_SYSTEM)
123 ? sstrerror (errno, errbuf, sizeof (errbuf))
124 : gai_strerror (ai_return));
125 return -1;
126 }
128 fd = -1;
129 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next) {
130 /* create our socket descriptor */
131 fd = socket (ai_ptr->ai_family, ai_ptr->ai_socktype, ai_ptr->ai_protocol);
132 if (fd < 0) {
133 char errbuf[1024];
134 ERROR ("memcached: socket: %s", sstrerror (errno, errbuf, sizeof (errbuf)));
135 continue;
136 }
138 /* connect to the memcached daemon */
139 status = (ssize_t) connect (fd, (struct sockaddr *) ai_ptr->ai_addr, ai_ptr->ai_addrlen);
140 if (status != 0) {
141 shutdown (fd, SHUT_RDWR);
142 close (fd);
143 fd = -1;
144 continue;
145 }
147 /* A socket could be opened and connecting succeeded. We're
148 * done. */
149 break;
150 }
152 freeaddrinfo (ai_list);
153 }
155 if (fd < 0) {
156 ERROR ("memcached: Could not connect to daemon.");
157 return -1;
158 }
160 if (send(fd, "stats\r\n", sizeof("stats\r\n") - 1, MSG_DONTWAIT) != (sizeof("stats\r\n") - 1)) {
161 ERROR ("memcached: Could not send command to the memcached daemon.");
162 return -1;
163 }
165 {
166 struct pollfd p;
167 int status;
169 memset (&p, 0, sizeof (p));
170 p.fd = fd;
171 p.events = POLLIN | POLLERR | POLLHUP;
172 p.revents = 0;
174 status = poll (&p, /* nfds = */ 1, /* timeout = */ 1000 * interval_g);
175 if (status <= 0)
176 {
177 if (status == 0)
178 {
179 ERROR ("memcached: poll(2) timed out after %i seconds.", interval_g);
180 }
181 else
182 {
183 char errbuf[1024];
184 ERROR ("memcached: poll(2) failed: %s",
185 sstrerror (errno, errbuf, sizeof (errbuf)));
186 }
187 shutdown (fd, SHUT_RDWR);
188 close (fd);
189 return (-1);
190 }
191 }
193 /* receive data from the memcached daemon */
194 memset (buffer, '\0', buffer_size);
196 buffer_fill = 0;
197 while ((status = recv (fd, buffer + buffer_fill, buffer_size - buffer_fill, MSG_DONTWAIT)) != 0) {
198 if (i > MEMCACHED_RETRY_COUNT) {
199 ERROR("recv() timed out");
200 break;
201 }
202 i++;
204 if (status == -1) {
205 char errbuf[1024];
207 if (errno == EAGAIN) {
208 continue;
209 }
211 ERROR ("memcached: Error reading from socket: %s",
212 sstrerror (errno, errbuf, sizeof (errbuf)));
213 shutdown(fd, SHUT_RDWR);
214 close (fd);
215 return -1;
216 }
217 buffer_fill += status;
219 if (buffer_fill > 3 && buffer[buffer_fill-5] == 'E' && buffer[buffer_fill-4] == 'N' && buffer[buffer_fill-3] == 'D') {
220 /* we got all the data */
221 break;
222 }
223 }
225 if (buffer_fill >= buffer_size) {
226 buffer[buffer_size - 1] = '\0';
227 WARNING ("memcached: Message from memcached has been truncated.");
228 } else if (buffer_fill == 0) {
229 WARNING ("memcached: Peer has unexpectedly shut down the socket. "
230 "Buffer: `%s'", buffer);
231 shutdown(fd, SHUT_RDWR);
232 close(fd);
233 return -1;
234 }
236 shutdown(fd, SHUT_RDWR);
237 close(fd);
238 return 0;
239 }
240 /* }}} */
242 static int memcached_config (const char *key, const char *value) /* {{{ */
243 {
244 if (strcasecmp (key, "Socket") == 0) {
245 if (memcached_socket != NULL) {
246 free (memcached_socket);
247 }
248 memcached_socket = strdup (value);
249 } else if (strcasecmp (key, "Host") == 0) {
250 if (memcached_host != NULL) {
251 free (memcached_host);
252 }
253 memcached_host = strdup (value);
254 } else if (strcasecmp (key, "Port") == 0) {
255 int port = (int) (atof (value));
256 if ((port > 0) && (port <= 65535)) {
257 ssnprintf (memcached_port, sizeof (memcached_port), "%i", port);
258 } else {
259 sstrncpy (memcached_port, value, sizeof (memcached_port));
260 }
261 } else {
262 return -1;
263 }
265 return 0;
266 }
267 /* }}} */
269 static void submit_counter (const char *type, const char *type_inst,
270 counter_t value) /* {{{ */
271 {
272 value_t values[1];
273 value_list_t vl = VALUE_LIST_INIT;
275 values[0].counter = value;
277 vl.values = values;
278 vl.values_len = 1;
279 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
280 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
281 sstrncpy (vl.type, type, sizeof (vl.type));
282 if (type_inst != NULL)
283 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
285 plugin_dispatch_values (&vl);
286 } /* void memcached_submit_cmd */
287 /* }}} */
289 static void submit_counter2 (const char *type, const char *type_inst,
290 counter_t value0, counter_t value1) /* {{{ */
291 {
292 value_t values[2];
293 value_list_t vl = VALUE_LIST_INIT;
295 values[0].counter = value0;
296 values[1].counter = value1;
298 vl.values = values;
299 vl.values_len = 2;
300 vl.time = time (NULL);
301 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
302 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
303 sstrncpy (vl.type, type, sizeof (vl.type));
304 if (type_inst != NULL)
305 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
307 plugin_dispatch_values (&vl);
308 } /* void memcached_submit_cmd */
309 /* }}} */
311 static void submit_gauge (const char *type, const char *type_inst,
312 gauge_t value) /* {{{ */
313 {
314 value_t values[1];
315 value_list_t vl = VALUE_LIST_INIT;
317 values[0].gauge = value;
319 vl.values = values;
320 vl.values_len = 1;
321 vl.time = time (NULL);
322 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
323 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
324 sstrncpy (vl.type, type, sizeof (vl.type));
325 if (type_inst != NULL)
326 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
328 plugin_dispatch_values (&vl);
329 }
330 /* }}} */
332 static void submit_gauge2 (const char *type, const char *type_inst,
333 gauge_t value0, gauge_t value1) /* {{{ */
334 {
335 value_t values[2];
336 value_list_t vl = VALUE_LIST_INIT;
338 values[0].gauge = value0;
339 values[1].gauge = value1;
341 vl.values = values;
342 vl.values_len = 2;
343 vl.time = time (NULL);
344 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
345 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
346 sstrncpy (vl.type, type, sizeof (vl.type));
347 if (type_inst != NULL)
348 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
350 plugin_dispatch_values (&vl);
351 }
352 /* }}} */
354 static int memcached_read (void) /* {{{ */
355 {
356 char buf[1024];
357 char *fields[3];
358 char *ptr;
359 char *line;
360 char *saveptr;
361 int fields_num;
363 gauge_t bytes_used = NAN;
364 gauge_t bytes_total = NAN;
365 gauge_t hits = NAN;
366 gauge_t gets = NAN;
367 counter_t rusage_user = 0;
368 counter_t rusage_syst = 0;
369 counter_t octets_rx = 0;
370 counter_t octets_tx = 0;
372 /* get data from daemon */
373 if (memcached_query_daemon (buf, sizeof (buf)) < 0) {
374 return -1;
375 }
377 #define FIELD_IS(cnst) \
378 (((sizeof(cnst) - 1) == name_len) && (strcmp (cnst, fields[1]) == 0))
380 ptr = buf;
381 saveptr = NULL;
382 while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL)
383 {
384 int name_len;
386 ptr = NULL;
388 fields_num = strsplit(line, fields, 3);
389 if (fields_num != 3)
390 continue;
392 name_len = strlen(fields[1]);
393 if (name_len == 0)
394 continue;
396 /*
397 * For an explanation on these fields please refer to
398 * <http://code.sixapart.com/svn/memcached/trunk/server/doc/protocol.txt>
399 */
401 /*
402 * CPU time consumed by the memcached process
403 */
404 if (FIELD_IS ("rusage_user"))
405 {
406 rusage_user = atoll (fields[2]);
407 }
408 else if (FIELD_IS ("rusage_system"))
409 {
410 rusage_syst = atoll(fields[2]);
411 }
413 /*
414 * Number of threads of this instance
415 */
416 else if (FIELD_IS ("threads"))
417 {
418 submit_gauge2 ("ps_count", NULL, NAN, atof (fields[2]));
419 }
421 /*
422 * Number of items stored
423 */
424 else if (FIELD_IS ("curr_items"))
425 {
426 submit_gauge ("memcached_items", "current", atof (fields[2]));
427 }
429 /*
430 * Number of bytes used and available (total - used)
431 */
432 else if (FIELD_IS ("bytes"))
433 {
434 bytes_used = atof (fields[2]);
435 }
436 else if (FIELD_IS ("limit_maxbytes"))
437 {
438 bytes_total = atof(fields[2]);
439 }
441 /*
442 * Connections
443 */
444 else if (FIELD_IS ("curr_connections"))
445 {
446 submit_gauge ("memcached_connections", "current", atof (fields[2]));
447 }
449 /*
450 * Commands
451 */
452 else if ((name_len > 4) && (strncmp (fields[1], "cmd_", 4) == 0))
453 {
454 const char *name = fields[1] + 4;
455 submit_counter ("memcached_command", name, atoll (fields[2]));
456 if (strcmp (name, "get") == 0)
457 gets = atof (fields[2]);
458 }
460 /*
461 * Operations on the cache, i. e. cache hits, cache misses and evictions of items
462 */
463 else if (FIELD_IS ("get_hits"))
464 {
465 submit_counter ("memcached_ops", "hits", atoll (fields[2]));
466 hits = atof (fields[2]);
467 }
468 else if (FIELD_IS ("get_misses"))
469 {
470 submit_counter ("memcached_ops", "misses", atoll (fields[2]));
471 }
472 else if (FIELD_IS ("evictions"))
473 {
474 submit_counter ("memcached_ops", "evictions", atoll (fields[2]));
475 }
477 /*
478 * Network traffic
479 */
480 else if (FIELD_IS ("bytes_read"))
481 {
482 octets_rx = atoll (fields[2]);
483 }
484 else if (FIELD_IS ("bytes_written"))
485 {
486 octets_tx = atoll (fields[2]);
487 }
488 } /* while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL) */
490 if (!isnan (bytes_used) && !isnan (bytes_total) && (bytes_used <= bytes_total))
491 submit_gauge2 ("df", "cache", bytes_used, bytes_total - bytes_used);
493 if ((rusage_user != 0) || (rusage_syst != 0))
494 submit_counter2 ("ps_cputime", NULL, rusage_user, rusage_syst);
496 if ((octets_rx != 0) || (octets_tx != 0))
497 submit_counter2 ("memcached_octets", NULL, octets_rx, octets_tx);
499 if (!isnan (gets) && !isnan (hits))
500 {
501 gauge_t rate = NAN;
503 if (gets != 0.0)
504 rate = 100.0 * hits / gets;
506 submit_gauge ("percent", "hitratio", rate);
507 }
509 return 0;
510 }
511 /* }}} */
513 void module_register (void) /* {{{ */
514 {
515 plugin_register_config ("memcached", memcached_config, config_keys, config_keys_num);
516 plugin_register_read ("memcached", memcached_read);
517 }
518 /* }}} */
520 /*
521 * Local variables:
522 * tab-width: 4
523 * c-basic-offset: 4
524 * End:
525 * vim600: sw=4 ts=4 fdm=marker noexpandtab
526 * vim<600: sw=4 ts=4 noexpandtab
527 */