1 /**
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 *
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 collectd.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 /* Hack to work around the missing define in AIX */
42 #ifndef MSG_DONTWAIT
43 # define MSG_DONTWAIT MSG_NONBLOCK
44 #endif
46 #define MEMCACHED_DEF_HOST "127.0.0.1"
47 #define MEMCACHED_DEF_PORT "11211"
49 #define MEMCACHED_RETRY_COUNT 100
51 static const char *config_keys[] =
52 {
53 "Socket",
54 "Host",
55 "Port"
56 };
57 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
59 static char *memcached_socket = NULL;
60 static char *memcached_host = NULL;
61 static char memcached_port[16];
63 static int memcached_query_daemon (char *buffer, int buffer_size) /* {{{ */
64 {
65 int fd;
66 ssize_t status;
67 int buffer_fill;
68 int i = 0;
70 if (memcached_socket != NULL) {
71 struct sockaddr_un serv_addr;
73 memset (&serv_addr, 0, sizeof (serv_addr));
74 serv_addr.sun_family = AF_UNIX;
75 sstrncpy (serv_addr.sun_path, memcached_socket,
76 sizeof (serv_addr.sun_path));
78 /* create our socket descriptor */
79 fd = socket (AF_UNIX, SOCK_STREAM, 0);
80 if (fd < 0) {
81 char errbuf[1024];
82 ERROR ("memcached: unix socket: %s", sstrerror (errno, errbuf,
83 sizeof (errbuf)));
84 return -1;
85 }
87 /* connect to the memcached daemon */
88 status = (ssize_t) connect (fd, (struct sockaddr *) &serv_addr,
89 sizeof (serv_addr));
90 if (status != 0) {
91 shutdown (fd, SHUT_RDWR);
92 close (fd);
93 fd = -1;
94 }
95 }
96 else { /* if (memcached_socket == NULL) */
97 const char *host;
98 const char *port;
100 struct addrinfo ai_hints;
101 struct addrinfo *ai_list, *ai_ptr;
102 int ai_return = 0;
104 memset (&ai_hints, '\0', sizeof (ai_hints));
105 ai_hints.ai_flags = 0;
106 #ifdef AI_ADDRCONFIG
107 /* ai_hints.ai_flags |= AI_ADDRCONFIG; */
108 #endif
109 ai_hints.ai_family = AF_INET;
110 ai_hints.ai_socktype = SOCK_STREAM;
111 ai_hints.ai_protocol = 0;
113 host = memcached_host;
114 if (host == NULL) {
115 host = MEMCACHED_DEF_HOST;
116 }
118 port = memcached_port;
119 if (strlen (port) == 0) {
120 port = MEMCACHED_DEF_PORT;
121 }
123 if ((ai_return = getaddrinfo (host, port, &ai_hints, &ai_list)) != 0) {
124 char errbuf[1024];
125 ERROR ("memcached: getaddrinfo (%s, %s): %s",
126 host, port,
127 (ai_return == EAI_SYSTEM)
128 ? sstrerror (errno, errbuf, sizeof (errbuf))
129 : gai_strerror (ai_return));
130 return -1;
131 }
133 fd = -1;
134 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next) {
135 /* create our socket descriptor */
136 fd = socket (ai_ptr->ai_family, ai_ptr->ai_socktype, ai_ptr->ai_protocol);
137 if (fd < 0) {
138 char errbuf[1024];
139 ERROR ("memcached: socket: %s", sstrerror (errno, errbuf, sizeof (errbuf)));
140 continue;
141 }
143 /* connect to the memcached daemon */
144 status = (ssize_t) connect (fd, (struct sockaddr *) ai_ptr->ai_addr, ai_ptr->ai_addrlen);
145 if (status != 0) {
146 shutdown (fd, SHUT_RDWR);
147 close (fd);
148 fd = -1;
149 continue;
150 }
152 /* A socket could be opened and connecting succeeded. We're
153 * done. */
154 break;
155 }
157 freeaddrinfo (ai_list);
158 }
160 if (fd < 0) {
161 ERROR ("memcached: Could not connect to daemon.");
162 return -1;
163 }
165 if (send(fd, "stats\r\n", sizeof("stats\r\n") - 1, MSG_DONTWAIT) != (sizeof("stats\r\n") - 1)) {
166 ERROR ("memcached: Could not send command to the memcached daemon.");
167 return -1;
168 }
170 {
171 struct pollfd p;
172 int status;
174 memset (&p, 0, sizeof (p));
175 p.fd = fd;
176 p.events = POLLIN | POLLERR | POLLHUP;
177 p.revents = 0;
179 status = poll (&p, /* nfds = */ 1,
180 /* timeout = */ CDTIME_T_TO_MS (interval_g));
181 if (status <= 0)
182 {
183 if (status == 0)
184 {
185 ERROR ("memcached: poll(2) timed out after %.3f seconds.",
186 CDTIME_T_TO_DOUBLE (interval_g));
187 }
188 else
189 {
190 char errbuf[1024];
191 ERROR ("memcached: poll(2) failed: %s",
192 sstrerror (errno, errbuf, sizeof (errbuf)));
193 }
194 shutdown (fd, SHUT_RDWR);
195 close (fd);
196 return (-1);
197 }
198 }
200 /* receive data from the memcached daemon */
201 memset (buffer, '\0', buffer_size);
203 buffer_fill = 0;
204 while ((status = recv (fd, buffer + buffer_fill, buffer_size - buffer_fill, MSG_DONTWAIT)) != 0) {
205 if (i > MEMCACHED_RETRY_COUNT) {
206 ERROR("recv() timed out");
207 break;
208 }
209 i++;
211 if (status == -1) {
212 char errbuf[1024];
214 if (errno == EAGAIN) {
215 continue;
216 }
218 ERROR ("memcached: Error reading from socket: %s",
219 sstrerror (errno, errbuf, sizeof (errbuf)));
220 shutdown(fd, SHUT_RDWR);
221 close (fd);
222 return -1;
223 }
224 buffer_fill += status;
226 if (buffer_fill > 3 && buffer[buffer_fill-5] == 'E' && buffer[buffer_fill-4] == 'N' && buffer[buffer_fill-3] == 'D') {
227 /* we got all the data */
228 break;
229 }
230 }
232 if (buffer_fill >= buffer_size) {
233 buffer[buffer_size - 1] = '\0';
234 WARNING ("memcached: Message from memcached has been truncated.");
235 } else if (buffer_fill == 0) {
236 WARNING ("memcached: Peer has unexpectedly shut down the socket. "
237 "Buffer: `%s'", buffer);
238 shutdown(fd, SHUT_RDWR);
239 close(fd);
240 return -1;
241 }
243 shutdown(fd, SHUT_RDWR);
244 close(fd);
245 return 0;
246 }
247 /* }}} */
249 static int memcached_config (const char *key, const char *value) /* {{{ */
250 {
251 if (strcasecmp (key, "Socket") == 0) {
252 if (memcached_socket != NULL) {
253 free (memcached_socket);
254 }
255 memcached_socket = strdup (value);
256 } else if (strcasecmp (key, "Host") == 0) {
257 if (memcached_host != NULL) {
258 free (memcached_host);
259 }
260 memcached_host = strdup (value);
261 } else if (strcasecmp (key, "Port") == 0) {
262 int port = (int) (atof (value));
263 if ((port > 0) && (port <= 65535)) {
264 ssnprintf (memcached_port, sizeof (memcached_port), "%i", port);
265 } else {
266 sstrncpy (memcached_port, value, sizeof (memcached_port));
267 }
268 } else {
269 return -1;
270 }
272 return 0;
273 }
274 /* }}} */
276 static void submit_derive (const char *type, const char *type_inst,
277 derive_t value) /* {{{ */
278 {
279 value_t values[1];
280 value_list_t vl = VALUE_LIST_INIT;
282 values[0].derive = value;
284 vl.values = values;
285 vl.values_len = 1;
286 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
287 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
288 sstrncpy (vl.type, type, sizeof (vl.type));
289 if (type_inst != NULL)
290 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
292 plugin_dispatch_values (&vl);
293 } /* void memcached_submit_cmd */
294 /* }}} */
296 static void submit_derive2 (const char *type, const char *type_inst,
297 derive_t value0, derive_t value1) /* {{{ */
298 {
299 value_t values[2];
300 value_list_t vl = VALUE_LIST_INIT;
302 values[0].derive = value0;
303 values[1].derive = value1;
305 vl.values = values;
306 vl.values_len = 2;
307 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
308 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
309 sstrncpy (vl.type, type, sizeof (vl.type));
310 if (type_inst != NULL)
311 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
313 plugin_dispatch_values (&vl);
314 } /* void memcached_submit_cmd */
315 /* }}} */
317 static void submit_gauge (const char *type, const char *type_inst,
318 gauge_t value) /* {{{ */
319 {
320 value_t values[1];
321 value_list_t vl = VALUE_LIST_INIT;
323 values[0].gauge = value;
325 vl.values = values;
326 vl.values_len = 1;
327 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
328 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
329 sstrncpy (vl.type, type, sizeof (vl.type));
330 if (type_inst != NULL)
331 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
333 plugin_dispatch_values (&vl);
334 }
335 /* }}} */
337 static void submit_gauge2 (const char *type, const char *type_inst,
338 gauge_t value0, gauge_t value1) /* {{{ */
339 {
340 value_t values[2];
341 value_list_t vl = VALUE_LIST_INIT;
343 values[0].gauge = value0;
344 values[1].gauge = value1;
346 vl.values = values;
347 vl.values_len = 2;
348 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
349 sstrncpy (vl.plugin, "memcached", sizeof (vl.plugin));
350 sstrncpy (vl.type, type, sizeof (vl.type));
351 if (type_inst != NULL)
352 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
354 plugin_dispatch_values (&vl);
355 }
356 /* }}} */
358 static int memcached_read (void) /* {{{ */
359 {
360 char buf[4096];
361 char *fields[3];
362 char *ptr;
363 char *line;
364 char *saveptr;
365 int fields_num;
367 gauge_t bytes_used = NAN;
368 gauge_t bytes_total = NAN;
369 gauge_t hits = NAN;
370 gauge_t gets = NAN;
371 derive_t rusage_user = 0;
372 derive_t rusage_syst = 0;
373 derive_t octets_rx = 0;
374 derive_t octets_tx = 0;
376 /* get data from daemon */
377 if (memcached_query_daemon (buf, sizeof (buf)) < 0) {
378 return -1;
379 }
381 #define FIELD_IS(cnst) \
382 (((sizeof(cnst) - 1) == name_len) && (strcmp (cnst, fields[1]) == 0))
384 ptr = buf;
385 saveptr = NULL;
386 while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL)
387 {
388 int name_len;
390 ptr = NULL;
392 fields_num = strsplit(line, fields, 3);
393 if (fields_num != 3)
394 continue;
396 name_len = strlen(fields[1]);
397 if (name_len == 0)
398 continue;
400 /*
401 * For an explanation on these fields please refer to
402 * <http://code.sixapart.com/svn/memcached/trunk/server/doc/protocol.txt>
403 */
405 /*
406 * CPU time consumed by the memcached process
407 */
408 if (FIELD_IS ("rusage_user"))
409 {
410 rusage_user = atoll (fields[2]);
411 }
412 else if (FIELD_IS ("rusage_system"))
413 {
414 rusage_syst = atoll(fields[2]);
415 }
417 /*
418 * Number of threads of this instance
419 */
420 else if (FIELD_IS ("threads"))
421 {
422 submit_gauge2 ("ps_count", NULL, NAN, atof (fields[2]));
423 }
425 /*
426 * Number of items stored
427 */
428 else if (FIELD_IS ("curr_items"))
429 {
430 submit_gauge ("memcached_items", "current", atof (fields[2]));
431 }
433 /*
434 * Number of bytes used and available (total - used)
435 */
436 else if (FIELD_IS ("bytes"))
437 {
438 bytes_used = atof (fields[2]);
439 }
440 else if (FIELD_IS ("limit_maxbytes"))
441 {
442 bytes_total = atof(fields[2]);
443 }
445 /*
446 * Connections
447 */
448 else if (FIELD_IS ("curr_connections"))
449 {
450 submit_gauge ("memcached_connections", "current", atof (fields[2]));
451 }
453 /*
454 * Commands
455 */
456 else if ((name_len > 4) && (strncmp (fields[1], "cmd_", 4) == 0))
457 {
458 const char *name = fields[1] + 4;
459 submit_derive ("memcached_command", name, atoll (fields[2]));
460 if (strcmp (name, "get") == 0)
461 gets = atof (fields[2]);
462 }
464 /*
465 * Operations on the cache, i. e. cache hits, cache misses and evictions of items
466 */
467 else if (FIELD_IS ("get_hits"))
468 {
469 submit_derive ("memcached_ops", "hits", atoll (fields[2]));
470 hits = atof (fields[2]);
471 }
472 else if (FIELD_IS ("get_misses"))
473 {
474 submit_derive ("memcached_ops", "misses", atoll (fields[2]));
475 }
476 else if (FIELD_IS ("evictions"))
477 {
478 submit_derive ("memcached_ops", "evictions", atoll (fields[2]));
479 }
481 /*
482 * Network traffic
483 */
484 else if (FIELD_IS ("bytes_read"))
485 {
486 octets_rx = atoll (fields[2]);
487 }
488 else if (FIELD_IS ("bytes_written"))
489 {
490 octets_tx = atoll (fields[2]);
491 }
492 } /* while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL) */
494 if (!isnan (bytes_used) && !isnan (bytes_total) && (bytes_used <= bytes_total))
495 submit_gauge2 ("df", "cache", bytes_used, bytes_total - bytes_used);
497 if ((rusage_user != 0) || (rusage_syst != 0))
498 submit_derive2 ("ps_cputime", NULL, rusage_user, rusage_syst);
500 if ((octets_rx != 0) || (octets_tx != 0))
501 submit_derive2 ("memcached_octets", NULL, octets_rx, octets_tx);
503 if (!isnan (gets) && !isnan (hits))
504 {
505 gauge_t rate = NAN;
507 if (gets != 0.0)
508 rate = 100.0 * hits / gets;
510 submit_gauge ("percent", "hitratio", rate);
511 }
513 return 0;
514 }
515 /* }}} */
517 void module_register (void) /* {{{ */
518 {
519 plugin_register_config ("memcached", memcached_config, config_keys, config_keys_num);
520 plugin_register_read ("memcached", memcached_read);
521 }
522 /* }}} */
524 /*
525 * Local variables:
526 * tab-width: 4
527 * c-basic-offset: 4
528 * End:
529 * vim600: sw=4 ts=4 fdm=marker noexpandtab
530 * vim<600: sw=4 ts=4 noexpandtab
531 */