1 /* Slowlog implements a system that is able to remember the latest N
2 * queries that took more than M microseconds to execute.
3 *
4 * The execution time to reach to be logged in the slow log is set
5 * using the 'slowlog-log-slower-than' config directive, that is also
6 * readable and writable using the CONFIG SET/GET command.
7 *
8 * The slow queries log is actually not "logged" in the Redis log file
9 * but is accessible thanks to the SLOWLOG command.
10 *
11 * ----------------------------------------------------------------------------
12 *
13 * Copyright (c) 2009-2012, Salvatore Sanfilippo <antirez at gmail dot com>
14 * All rights reserved.
15 *
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions are met:
18 *
19 * * Redistributions of source code must retain the above copyright notice,
20 * this list of conditions and the following disclaimer.
21 * * Redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution.
24 * * Neither the name of Redis nor the names of its contributors may be used
25 * to endorse or promote products derived from this software without
26 * specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
29 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
32 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
33 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
34 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
35 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
36 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
37 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
38 * POSSIBILITY OF SUCH DAMAGE.
39 */
40
41
42 #include "server.h"
43 #include "slowlog.h"
44
45 /* Create a new slowlog entry.
46 * Incrementing the ref count of all the objects retained is up to
47 * this function. */
slowlogCreateEntry(robj ** argv,int argc,long long duration)48 slowlogEntry *slowlogCreateEntry(robj **argv, int argc, long long duration) {
49 slowlogEntry *se = zmalloc(sizeof(*se));
50 int j, slargc = argc;
51
52 if (slargc > SLOWLOG_ENTRY_MAX_ARGC) slargc = SLOWLOG_ENTRY_MAX_ARGC;
53 se->argc = slargc;
54 se->argv = zmalloc(sizeof(robj*)*slargc);
55 for (j = 0; j < slargc; j++) {
56 /* Logging too many arguments is a useless memory waste, so we stop
57 * at SLOWLOG_ENTRY_MAX_ARGC, but use the last argument to specify
58 * how many remaining arguments there were in the original command. */
59 if (slargc != argc && j == slargc-1) {
60 se->argv[j] = createObject(OBJ_STRING,
61 sdscatprintf(sdsempty(),"... (%d more arguments)",
62 argc-slargc+1));
63 } else {
64 /* Trim too long strings as well... */
65 if (argv[j]->type == OBJ_STRING &&
66 sdsEncodedObject(argv[j]) &&
67 sdslen(argv[j]->ptr) > SLOWLOG_ENTRY_MAX_STRING)
68 {
69 sds s = sdsnewlen(argv[j]->ptr, SLOWLOG_ENTRY_MAX_STRING);
70
71 s = sdscatprintf(s,"... (%lu more bytes)",
72 (unsigned long)
73 sdslen(argv[j]->ptr) - SLOWLOG_ENTRY_MAX_STRING);
74 se->argv[j] = createObject(OBJ_STRING,s);
75 } else {
76 se->argv[j] = argv[j];
77 incrRefCount(argv[j]);
78 }
79 }
80 }
81 se->time = time(NULL);
82 se->duration = duration;
83 se->id = server.slowlog_entry_id++;
84 return se;
85 }
86
87 /* Free a slow log entry. The argument is void so that the prototype of this
88 * function matches the one of the 'free' method of adlist.c.
89 *
90 * This function will take care to release all the retained object. */
slowlogFreeEntry(void * septr)91 void slowlogFreeEntry(void *septr) {
92 slowlogEntry *se = septr;
93 int j;
94
95 for (j = 0; j < se->argc; j++)
96 decrRefCount(se->argv[j]);
97 zfree(se->argv);
98 zfree(se);
99 }
100
101 /* Initialize the slow log. This function should be called a single time
102 * at server startup. */
slowlogInit(void)103 void slowlogInit(void) {
104 server.slowlog = listCreate();
105 server.slowlog_entry_id = 0;
106 listSetFreeMethod(server.slowlog,slowlogFreeEntry);
107 }
108
109 /* Push a new entry into the slow log.
110 * This function will make sure to trim the slow log accordingly to the
111 * configured max length. */
slowlogPushEntryIfNeeded(robj ** argv,int argc,long long duration)112 void slowlogPushEntryIfNeeded(robj **argv, int argc, long long duration) {
113 if (server.slowlog_log_slower_than < 0) return; /* Slowlog disabled */
114 if (duration >= server.slowlog_log_slower_than)
115 listAddNodeHead(server.slowlog,slowlogCreateEntry(argv,argc,duration));
116
117 /* Remove old entries if needed. */
118 while (listLength(server.slowlog) > server.slowlog_max_len)
119 listDelNode(server.slowlog,listLast(server.slowlog));
120 }
121
122 /* Remove all the entries from the current slow log. */
slowlogReset(void)123 void slowlogReset(void) {
124 while (listLength(server.slowlog) > 0)
125 listDelNode(server.slowlog,listLast(server.slowlog));
126 }
127
128 /* The SLOWLOG command. Implements all the subcommands needed to handle the
129 * Redis slow log. */
slowlogCommand(client * c)130 void slowlogCommand(client *c) {
131 if (c->argc == 2 && !strcasecmp(c->argv[1]->ptr,"reset")) {
132 slowlogReset();
133 addReply(c,shared.ok);
134 } else if (c->argc == 2 && !strcasecmp(c->argv[1]->ptr,"len")) {
135 addReplyLongLong(c,listLength(server.slowlog));
136 } else if ((c->argc == 2 || c->argc == 3) &&
137 !strcasecmp(c->argv[1]->ptr,"get"))
138 {
139 long count = 10, sent = 0;
140 listIter li;
141 void *totentries;
142 listNode *ln;
143 slowlogEntry *se;
144
145 if (c->argc == 3 &&
146 getLongFromObjectOrReply(c,c->argv[2],&count,NULL) != C_OK)
147 return;
148
149 listRewind(server.slowlog,&li);
150 totentries = addDeferredMultiBulkLength(c);
151 while(count-- && (ln = listNext(&li))) {
152 int j;
153
154 se = ln->value;
155 addReplyMultiBulkLen(c,4);
156 addReplyLongLong(c,se->id);
157 addReplyLongLong(c,se->time);
158 addReplyLongLong(c,se->duration);
159 addReplyMultiBulkLen(c,se->argc);
160 for (j = 0; j < se->argc; j++)
161 addReplyBulk(c,se->argv[j]);
162 sent++;
163 }
164 setDeferredMultiBulkLength(c,totentries,sent);
165 } else {
166 addReplyError(c,
167 "Unknown SLOWLOG subcommand or wrong # of args. Try GET, RESET, LEN.");
168 }
169 }
170