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 n;
132 p.fd = fd;
133 p.events = POLLIN|POLLERR|POLLHUP;
134 p.revents = 0;
136 n = poll(&p, 1, 3);
138 if (n <= 0) {
139 ERROR ("memcached: poll() failed or timed out");
140 return -1;
141 }
142 }
144 /* receive data from the memcached daemon */
145 memset (buffer, '\0', buffer_size);
147 buffer_fill = 0;
148 while ((status = recv (fd, buffer + buffer_fill, buffer_size - buffer_fill, MSG_DONTWAIT)) != 0) {
149 if (i > MEMCACHED_RETRY_COUNT) {
150 ERROR("recv() timed out");
151 break;
152 }
153 i++;
155 if (status == -1) {
156 char errbuf[1024];
158 if (errno == EAGAIN) {
159 continue;
160 }
162 ERROR ("memcached: Error reading from socket: %s",
163 sstrerror (errno, errbuf, sizeof (errbuf)));
164 shutdown(fd, SHUT_RDWR);
165 close (fd);
166 return -1;
167 }
168 buffer_fill += status;
170 if (buffer_fill > 3 && buffer[buffer_fill-5] == 'E' && buffer[buffer_fill-4] == 'N' && buffer[buffer_fill-3] == 'D') {
171 /* we got all the data */
172 break;
173 }
174 }
176 if (buffer_fill >= buffer_size) {
177 buffer[buffer_size - 1] = '\0';
178 WARNING ("memcached: Message from memcached has been truncated.");
179 } else if (buffer_fill == 0) {
180 WARNING ("memcached: Peer has unexpectedly shut down the socket. "
181 "Buffer: `%s'", buffer);
182 shutdown(fd, SHUT_RDWR);
183 close(fd);
184 return -1;
185 }
187 shutdown(fd, SHUT_RDWR);
188 close(fd);
189 return 0;
190 }
191 /* }}} */
193 static int memcached_config (const char *key, const char *value) /* {{{ */
194 {
195 if (strcasecmp (key, "Host") == 0) {
196 if (memcached_host != NULL) {
197 free (memcached_host);
198 }
199 memcached_host = strdup (value);
200 } else if (strcasecmp (key, "Port") == 0) {
201 int port = (int) (atof (value));
202 if ((port > 0) && (port <= 65535)) {
203 snprintf (memcached_port, sizeof (memcached_port), "%i", port);
204 } else {
205 strncpy (memcached_port, value, sizeof (memcached_port));
206 }
207 memcached_port[sizeof (memcached_port) - 1] = '\0';
208 } else {
209 return -1;
210 }
212 return 0;
213 }
214 /* }}} */
216 static void submit_counter (const char *type, const char *type_inst,
217 counter_t value) /* {{{ */
218 {
219 value_t values[1];
220 value_list_t vl = VALUE_LIST_INIT;
222 values[0].counter = value;
224 vl.values = values;
225 vl.values_len = 1;
226 vl.time = time (NULL);
227 strcpy (vl.host, hostname_g);
228 strcpy (vl.plugin, "memcached");
229 if (type_inst != NULL)
230 {
231 strncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
232 vl.type_instance[sizeof (vl.type_instance) - 1] = '\0';
233 }
235 plugin_dispatch_values (type, &vl);
236 } /* void memcached_submit_cmd */
237 /* }}} */
239 static void submit_counter2 (const char *type, const char *type_inst,
240 counter_t value0, counter_t value1) /* {{{ */
241 {
242 value_t values[2];
243 value_list_t vl = VALUE_LIST_INIT;
245 values[0].counter = value0;
246 values[1].counter = value1;
248 vl.values = values;
249 vl.values_len = 2;
250 vl.time = time (NULL);
251 strcpy (vl.host, hostname_g);
252 strcpy (vl.plugin, "memcached");
253 if (type_inst != NULL)
254 {
255 strncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
256 vl.type_instance[sizeof (vl.type_instance) - 1] = '\0';
257 }
259 plugin_dispatch_values (type, &vl);
260 } /* void memcached_submit_cmd */
261 /* }}} */
263 static void submit_gauge (const char *type, const char *type_inst,
264 gauge_t value) /* {{{ */
265 {
266 value_t values[1];
267 value_list_t vl = VALUE_LIST_INIT;
269 values[0].gauge = value;
271 vl.values = values;
272 vl.values_len = 1;
273 vl.time = time (NULL);
274 strcpy (vl.host, hostname_g);
275 strcpy (vl.plugin, "memcached");
276 if (type_inst != NULL)
277 {
278 strncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
279 vl.type_instance[sizeof (vl.type_instance) - 1] = '\0';
280 }
282 plugin_dispatch_values (type, &vl);
283 }
284 /* }}} */
286 static void submit_gauge2 (const char *type, const char *type_inst,
287 gauge_t value0, gauge_t value1) /* {{{ */
288 {
289 value_t values[2];
290 value_list_t vl = VALUE_LIST_INIT;
292 values[0].gauge = value0;
293 values[1].gauge = value1;
295 vl.values = values;
296 vl.values_len = 2;
297 vl.time = time (NULL);
298 strcpy (vl.host, hostname_g);
299 strcpy (vl.plugin, "memcached");
300 if (type_inst != NULL)
301 {
302 strncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
303 vl.type_instance[sizeof (vl.type_instance) - 1] = '\0';
304 }
306 plugin_dispatch_values (type, &vl);
307 }
308 /* }}} */
310 static int memcached_read (void) /* {{{ */
311 {
312 char buf[1024];
313 char *fields[3];
314 char *ptr;
315 char *line;
316 char *saveptr;
317 int fields_num;
319 gauge_t bytes_used = NAN;
320 gauge_t bytes_total = NAN;
321 counter_t rusage_user = 0;
322 counter_t rusage_syst = 0;
323 counter_t octets_rx = 0;
324 counter_t octets_tx = 0;
326 /* get data from daemon */
327 if (memcached_query_daemon (buf, sizeof (buf)) < 0) {
328 return -1;
329 }
331 #define FIELD_IS(cnst) \
332 (((sizeof(cnst) - 1) == name_len) && (strcmp (cnst, fields[1]) == 0))
334 ptr = buf;
335 saveptr = NULL;
336 while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL)
337 {
338 int name_len;
340 ptr = NULL;
342 fields_num = strsplit(line, fields, 3);
343 if (fields_num != 3)
344 continue;
346 name_len = strlen(fields[1]);
347 if (name_len == 0)
348 continue;
350 /*
351 * For an explanation on these fields please refer to
352 * <http://code.sixapart.com/svn/memcached/trunk/server/doc/protocol.txt>
353 */
355 /*
356 * CPU time consumed by the memcached process
357 */
358 if (FIELD_IS ("rusage_user"))
359 {
360 rusage_user = atoll (fields[2]);
361 }
362 else if (FIELD_IS ("rusage_system"))
363 {
364 rusage_syst = atoll(fields[2]);
365 }
367 /*
368 * Number of threads of this instance
369 */
370 else if (FIELD_IS ("threads"))
371 {
372 submit_gauge2 ("ps_count", NULL, NAN, atof (fields[2]));
373 }
375 /*
376 * Number of items stored
377 */
378 else if (FIELD_IS ("curr_items"))
379 {
380 submit_gauge ("memcached_items", "current", atof (fields[2]));
381 }
382 /*
383 else if (FIELD_IS ("total_items"))
384 {
385 total_items = atoll(fields[2]);
386 }
387 */
389 /*
390 * Number of bytes used and available (total - used)
391 */
392 else if (FIELD_IS ("bytes"))
393 {
394 bytes_used = atof (fields[2]);
395 }
396 else if (FIELD_IS ("limit_maxbytes"))
397 {
398 bytes_total = atof(fields[2]);
399 }
401 /*
402 * Connections
403 */
404 else if (FIELD_IS ("curr_connections"))
405 {
406 submit_gauge ("memcached_connections", "current", atof (fields[2]));
407 }
408 /*
409 else if (FIELD_IS("total_connections"))
410 {
411 total_connections = atoll(fields[2]);
412 }
413 */
415 /*
416 * ``Number of connection structures allocated by the server''
417 else if (FIELD_IS ("connection_structures"))
418 {
419 connection_structures = atof(fields[2]);
420 }
421 */
423 /*
424 * Commands
425 */
426 else if ((name_len > 4) && (strncmp (fields[1], "cmd_", 4) == 0))
427 {
428 const char *name = fields[1] + 4;
429 submit_counter ("memcached_command", name, atoll (fields[2]));
430 }
432 /*
433 * Operations on the cache, i. e. cache hits, cache misses and evictions of items
434 */
435 else if (FIELD_IS ("get_hits"))
436 {
437 submit_counter ("memcached_ops", "hits", atoll (fields[2]));
438 }
439 else if (FIELD_IS ("get_misses"))
440 {
441 submit_counter ("memcached_ops", "misses", atoll (fields[2]));
442 }
443 else if (FIELD_IS ("evictions"))
444 {
445 submit_counter ("memcached_ops", "evictions", atoll (fields[2]));
446 }
448 /*
449 * Network traffic
450 */
451 else if (FIELD_IS ("bytes_read"))
452 {
453 octets_rx = atoll (fields[2]);
454 }
455 else if (FIELD_IS ("bytes_written"))
456 {
457 octets_tx = atoll (fields[2]);
458 }
459 } /* while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL) */
461 if (!isnan (bytes_used) && !isnan (bytes_total) && (bytes_used <= bytes_total))
462 submit_gauge2 ("df", "cache", bytes_used, bytes_total - bytes_used);
464 if ((rusage_user != 0) || (rusage_syst != 0))
465 submit_counter2 ("ps_cputime", NULL, rusage_user, rusage_syst);
467 if ((octets_rx != 0) || (octets_tx != 0))
468 submit_counter2 ("memcached_octets", NULL, octets_rx, octets_tx);
470 return 0;
471 }
472 /* }}} */
474 void module_register (void) /* {{{ */
475 {
476 plugin_register_config ("memcached", memcached_config, config_keys, config_keys_num);
477 plugin_register_read ("memcached", memcached_read);
478 }
479 /* }}} */
481 /*
482 * Local variables:
483 * tab-width: 4
484 * c-basic-offset: 4
485 * End:
486 * vim600: sw=4 ts=4 fdm=marker
487 * vim<600: sw=4 ts=4
488 */