Redis默认配置文件redis.conf详解

￡神魔★判官ぃ 2022-06-10 10:53 413阅读 0赞

1.  \# Redis配置文件样例
2.  
3.  \# Note on units: when memory size is needed, it is possible to specifiy
4.  \# it in the usual form of 1k 5GB 4M and so forth:
5.  \#
6.  \# 1k => 1000 bytes
7.  \# 1kb => 1024 bytes
8.  \# 1m => 1000000 bytes
9.  \# 1mb => 1024\*1024 bytes
10. \# 1g => 1000000000 bytes
11. \# 1gb => 1024\*1024\*1024 bytes
12. \#
13. \# units are case insensitive so 1GB 1Gb 1gB are all the same.
14. 
15. \# Redis默认不是以守护进程的方式运行，可以通过该配置项修改，使用yes启用守护进程
16. \# 启用守护进程后，Redis会把pid写到一个pidfile中，在/var/run/redis.pid
17. daemonize no
18. 
19. \# 当Redis以守护进程方式运行时，Redis默认会把pid写入/var/run/redis.pid文件，可以通过pidfile指定
20. pidfile /var/run/redis.pid
21. 
22. \# 指定Redis监听端口，默认端口为6379
23. \# 如果指定0端口，表示Redis不监听TCP连接
24. port 6379
25. 
26. \# 绑定的主机地址
27. \# 你可以绑定单一接口，如果没有绑定，所有接口都会监听到来的连接
28. \# bind 127.0.0.1
29. 
30. \# Specify the path for the unix socket that will be used to listen for
31. \# incoming connections. There is no default, so Redis will not listen
32. \# on a unix socket when not specified.
33. \#
34. \# unixsocket /tmp/redis.sock
35. \# unixsocketperm 755
36. 
37. \# 当客户端闲置多长时间后关闭连接，如果指定为0，表示关闭该功能
38. timeout 0
39. 
40. \# 指定日志记录级别，Redis总共支持四个级别：debug、verbose、notice、warning，默认为verbose
41. \# debug (很多信息, 对开发／测试比较有用)
42. \# verbose (many rarely useful info, but not a mess like the debug level)
43. \# notice (moderately verbose, what you want in production probably)
44. \# warning (only very important / critical messages are logged)
45. loglevel verbose
46. 
47. \# 日志记录方式，默认为标准输出，如果配置为redis为守护进程方式运行，而这里又配置为标准输出，则日志将会发送给/dev/null
48. logfile stdout
49. 
50. \# To enable logging to the system logger, just set 'syslog-enabled' to yes,
51. \# and optionally update the other syslog parameters to suit your needs.
52. \# syslog-enabled no
53. 
54. \# Specify the syslog identity.
55. \# syslog-ident redis
56. 
57. \# Specify the syslog facility. Must be USER or between LOCAL0-LOCAL7.
58. \# syslog-facility local0
59. 
60. \# 设置数据库的数量，默认数据库为0，可以使用select <dbid>命令在连接上指定数据库id
61. \# dbid是从0到‘databases’-1的数目
62. databases 16
63. 
64. \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\# SNAPSHOTTING \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#
65. \# 指定在多长时间内，有多少次更新操作，就将数据同步到数据文件，可以多个条件配合
66. \# Save the DB on disk:
67. \#
68. \# save <seconds> <changes>
69. \#
70. \# Will save the DB if both the given number of seconds and the given
71. \# number of write operations against the DB occurred.
72. \#
73. \# 满足以下条件将会同步数据:
74. \# 900秒（15分钟）内有1个更改
75. \# 300秒（5分钟）内有10个更改
76. \# 60秒内有10000个更改
77. \# Note: 可以把所有“save”行注释掉，这样就取消同步操作了
78. 
79. save 900 1
80. save 300 10
81. save 60 10000
82. 
83. \# 指定存储至本地数据库时是否压缩数据，默认为yes，Redis采用LZF压缩，如果为了节省CPU时间，可以关闭该选项，但会导致数据库文件变的巨大
84. rdbcompression yes
85. 
86. \# 指定本地数据库文件名，默认值为dump.rdb
87. dbfilename dump.rdb
88. 
89. \# 工作目录.
90. \# 指定本地数据库存放目录，文件名由上一个dbfilename配置项指定
91. \#
92. \# Also the Append Only File will be created inside this directory.
93. \#
94. \# 注意，这里只能指定一个目录，不能指定文件名
95. dir ./
96. 
97. \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\# REPLICATION \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#
98. 
99. \# 主从复制。使用slaveof从 Redis服务器复制一个Redis实例。注意，该配置仅限于当前slave有效
100. \# so for example it is possible to configure the slave to save the DB with a
101. \# different interval, or to listen to another port, and so on.
102. \# 设置当本机为slav服务时，设置master服务的ip地址及端口，在Redis启动时，它会自动从master进行数据同步
103. \# slaveof <masterip> <masterport>
104. 
105. 
106. \# 当master服务设置了密码保护时，slav服务连接master的密码
107. \# 下文的“requirepass”配置项可以指定密码
108. \# masterauth <master-password>
109. 
110. \# When a slave lost the connection with the master, or when the replication
111. \# is still in progress, the slave can act in two different ways:
112. \#
113. \# 1) if slave-serve-stale-data is set to 'yes' (the default) the slave will
114. \# still reply to client requests, possibly with out of data data, or the
115. \# data set may just be empty if this is the first synchronization.
116. \#
117. \# 2) if slave-serve-stale data is set to 'no' the slave will reply with
118. \# an error "SYNC with master in progress" to all the kind of commands
119. \# but to INFO and SLAVEOF.
120. \#
121. slave-serve-stale-data yes
122. 
123. \# Slaves send PINGs to server in a predefined interval. It's possible to change
124. \# this interval with the repl\_ping\_slave\_period option. The default value is 10
125. \# seconds.
126. \#
127. \# repl-ping-slave-period 10
128. 
129. \# The following option sets a timeout for both Bulk transfer I/O timeout and
130. \# master data or ping response timeout. The default value is 60 seconds.
131. \#
132. \# It is important to make sure that this value is greater than the value
133. \# specified for repl-ping-slave-period otherwise a timeout will be detected
134. \# every time there is low traffic between the master and the slave.
135. \#
136. \# repl-timeout 60
137. 
138. \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\# SECURITY \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#
139. 
140. \# Warning: since Redis is pretty fast an outside user can try up to
141. \# 150k passwords per second against a good box. This means that you should
142. \# use a very strong password otherwise it will be very easy to break.
143. \# 设置Redis连接密码，如果配置了连接密码，客户端在连接Redis时需要通过auth <password>命令提供密码，默认关闭
144. \# requirepass foobared
145. 
146. \# Command renaming.
147. \#
148. \# It is possilbe to change the name of dangerous commands in a shared
149. \# environment. For instance the CONFIG command may be renamed into something
150. \# of hard to guess so that it will be still available for internal-use
151. \# tools but not available for general clients.
152. \#
153. \# Example:
154. \#
155. \# rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52
156. \#
157. \# It is also possilbe to completely kill a command renaming it into
158. \# an empty string:
159. \#
160. \# rename-command CONFIG ""
161. 
162. \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\# LIMITS \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#
163. 
164. \# 设置同一时间最大客户端连接数，默认无限制，Redis可以同时打开的客户端连接数为Redis进程可以打开的最大文件描述符数，
165. \# 如果设置maxclients 0，表示不作限制。当客户端连接数到达限制时，Redis会关闭新的连接并向客户端返回max Number of clients reached错误信息
166. \# maxclients 128
167. 
168. \# Don't use more memory than the specified amount of bytes.
169. \# When the memory limit is reached Redis will try to remove keys with an
170. \# EXPIRE set. It will try to start freeing keys that are going to expire
171. \# in little time and preserve keys with a longer time to live.
172. \# Redis will also try to remove objects from free lists if possible.
173. \#
174. \# If all this fails, Redis will start to reply with errors to commands
175. \# that will use more memory, like SET, LPUSH, and so on, and will continue
176. \# to reply to most read-only commands like GET.
177. \#
178. \# WARNING: maxmemory can be a good idea mainly if you want to use Redis as a
179. \# 'state' server or cache, not as a real DB. When Redis is used as a real
180. \# database the memory usage will grow over the weeks, it will be obvious if
181. \# it is going to use too much memory in the long run, and you'll have the time
182. \# to upgrade. With maxmemory after the limit is reached you'll start to get
183. \# errors for write operations, and this may even lead to DB inconsistency.
184. \# 指定Redis最大内存限制，Redis在启动时会把数据加载到内存中，达到最大内存后，Redis会先尝试清除已到期或即将到期的Key，
185. \# 当此方法处理后，仍然到达最大内存设置，将无法再进行写入操作，但仍然可以进行读取操作。
186. \# Redis新的vm机制，会把Key存放内存，Value会存放在swap区
187. \# maxmemory <bytes>
188. 
189. \# MAXMEMORY POLICY: how Redis will select what to remove when maxmemory
190. \# is reached? You can select among five behavior:
191. \#
192. \# volatile-lru -> remove the key with an expire set using an LRU algorithm
193. \# allkeys-lru -> remove any key accordingly to the LRU algorithm
194. \# volatile-random -> remove a random key with an expire set
195. \# allkeys->random -> remove a random key, any key
196. \# volatile-ttl -> remove the key with the nearest expire time (minor TTL)
197. \# noeviction -> don't expire at all, just return an error on write operations
198. \#
199. \# Note: with all the kind of policies, Redis will return an error on write
200. \# operations, when there are not suitable keys for eviction.
201. \#
202. \# At the date of writing this commands are: set setnx setex append
203. \# incr decr rpush lpush rpushx lpushx linsert lset rpoplpush sadd
204. \# sinter sinterstore sunion sunionstore sdiff sdiffstore zadd zincrby
205. \# zunionstore zinterstore hset hsetnx hmset hincrby incrby decrby
206. \# getset mset msetnx exec sort
207. \#
208. \# The default is:
209. \#
210. \# maxmemory-policy volatile-lru
211. 
212. \# LRU and minimal TTL algorithms are not precise algorithms but approximated
213. \# algorithms (in order to save memory), so you can select as well the sample
214. \# size to check. For instance for default Redis will check three keys and
215. \# pick the one that was used less recently, you can change the sample size
216. \# using the following configuration directive.
217. \#
218. \# maxmemory-samples 3
219. 
220. \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\# APPEND ONLY MODE \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#
221. 
222. \#
223. \# Note that you can have both the async dumps and the append only file if you
224. \# like (you have to comment the "save" statements above to disable the dumps).
225. \# Still if append only mode is enabled Redis will load the data from the
226. \# log file at startup ignoring the dump.rdb file.
227. \# 指定是否在每次更新操作后进行日志记录，Redis在默认情况下是异步的把数据写入磁盘，如果不开启，可能会在断电时导致一段时间内的数据丢失。
228. \# 因为redis本身同步数据文件是按上面save条件来同步的，所以有的数据会在一段时间内只存在于内存中。默认为no
229. \# IMPORTANT: Check the BGREWRITEAOF to check how to rewrite the append
230. \# log file in background when it gets too big.
231. 
232. appendonly no
233. 
234. \# 指定更新日志文件名，默认为appendonly.aof
235. \# appendfilename appendonly.aof
236. 
237. \# The fsync() call tells the Operating System to actually write data on disk
238. \# instead to wait for more data in the output buffer. Some OS will really flush
239. \# data on disk, some other OS will just try to do it ASAP.
240. 
241. \# 指定更新日志条件，共有3个可选值：
242. \# no:表示等操作系统进行数据缓存同步到磁盘（快）
243. \# always:表示每次更新操作后手动调用fsync()将数据写到磁盘（慢，安全）
244. \# everysec:表示每秒同步一次（折衷，默认值）
245. 
246. appendfsync everysec
247. \# appendfsync no
248. 
249. \# When the AOF fsync policy is set to always or everysec, and a background
250. \# saving process (a background save or AOF log background rewriting) is
251. \# performing a lot of I/O against the disk, in some Linux configurations
252. \# Redis may block too long on the fsync() call. Note that there is no fix for
253. \# this currently, as even performing fsync in a different thread will block
254. \# our synchronous write(2) call.
255. \#
256. \# In order to mitigate this problem it's possible to use the following option
257. \# that will prevent fsync() from being called in the main process while a
258. \# BGSAVE or BGREWRITEAOF is in progress.
259. \#
260. \# This means that while another child is saving the durability of Redis is
261. \# the same as "appendfsync none", that in pratical terms means that it is
262. \# possible to lost up to 30 seconds of log in the worst scenario (with the
263. \# default Linux settings).
264. \#
265. \# If you have latency problems turn this to "yes". Otherwise leave it as
266. \# "no" that is the safest pick from the point of view of durability.
267. no-appendfsync-on-rewrite no
268. 
269. \# Automatic rewrite of the append only file.
270. \# Redis is able to automatically rewrite the log file implicitly calling
271. \# BGREWRITEAOF when the AOF log size will growth by the specified percentage.
272. \#
273. \# This is how it works: Redis remembers the size of the AOF file after the
274. \# latest rewrite (or if no rewrite happened since the restart, the size of
275. \# the AOF at startup is used).
276. \#
277. \# This base size is compared to the current size. If the current size is
278. \# bigger than the specified percentage, the rewrite is triggered. Also
279. \# you need to specify a minimal size for the AOF file to be rewritten, this
280. \# is useful to avoid rewriting the AOF file even if the percentage increase
281. \# is reached but it is still pretty small.
282. \#
283. \# Specify a precentage of zero in order to disable the automatic AOF
284. \# rewrite feature.
285. 
286. auto-aof-rewrite-percentage 100
287. auto-aof-rewrite-min-size 64mb
288. 
289. \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\# SLOW LOG \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#
290. 
291. \# The Redis Slow Log is a system to log queries that exceeded a specified
292. \# execution time. The execution time does not include the I/O operations
293. \# like talking with the client, sending the reply and so forth,
294. \# but just the time needed to actually execute the command (this is the only
295. \# stage of command execution where the thread is blocked and can not serve
296. \# other requests in the meantime).
297. \#
298. \# You can configure the slow log with two parameters: one tells Redis
299. \# what is the execution time, in microseconds, to exceed in order for the
300. \# command to get logged, and the other parameter is the length of the
301. \# slow log. When a new command is logged the oldest one is removed from the
302. \# queue of logged commands.
303. 
304. \# The following time is expressed in microseconds, so 1000000 is equivalent
305. \# to one second. Note that a negative number disables the slow log, while
306. \# a value of zero forces the logging of every command.
307. slowlog-log-slower-than 10000
308. 
309. \# There is no limit to this length. Just be aware that it will consume memory.
310. \# You can reclaim memory used by the slow log with SLOWLOG RESET.
311. slowlog-max-len 1024
312. 
313. \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\# VIRTUAL MEMORY \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#
314. 
315. \#\#\# WARNING! Virtual Memory is deprecated in Redis 2.4
316. \#\#\# The use of Virtual Memory is strongly discouraged.
317. 
318. \#\#\# WARNING! Virtual Memory is deprecated in Redis 2.4
319. \#\#\# The use of Virtual Memory is strongly discouraged.
320. 
321. \# Virtual Memory allows Redis to work with datasets bigger than the actual
322. \# amount of RAM needed to hold the whole dataset in memory.
323. \# In order to do so very used keys are taken in memory while the other keys
324. \# are swapped into a swap file, similarly to what operating systems do
325. \# with memory pages.
326. \# 指定是否启用虚拟内存机制，默认值为no，
327. \# VM机制将数据分页存放，由Redis将访问量较少的页即冷数据swap到磁盘上，访问多的页面由磁盘自动换出到内存中
328. \# 把vm-enabled设置为yes，根据需要设置好接下来的三个VM参数，就可以启动VM了
329. vm-enabled no
330. \# vm-enabled yes
331. 
332. \# This is the path of the Redis swap file. As you can guess, swap files
333. \# can't be shared by different Redis instances, so make sure to use a swap
334. \# file for every redis process you are running. Redis will complain if the
335. \# swap file is already in use.
336. \#
337. \# Redis交换文件最好的存储是SSD（固态硬盘）
338. \# 虚拟内存文件路径，默认值为/tmp/redis.swap，不可多个Redis实例共享
339. \# \*\*\* WARNING \*\*\* if you are using a shared hosting the default of putting
340. \# the swap file under /tmp is not secure. Create a dir with access granted
341. \# only to Redis user and configure Redis to create the swap file there.
342. vm-swap-file /tmp/redis.swap
343. 
344. \# With vm-max-memory 0 the system will swap everything it can. Not a good
345. \# default, just specify the max amount of RAM you can in bytes, but it's
346. \# better to leave some margin. For instance specify an amount of RAM
347. \# that's more or less between 60 and 80% of your free RAM.
348. \# 将所有大于vm-max-memory的数据存入虚拟内存，无论vm-max-memory设置多少，所有索引数据都是内存存储的（Redis的索引数据就是keys）
349. \# 也就是说当vm-max-memory设置为0的时候，其实是所有value都存在于磁盘。默认值为0
350. vm-max-memory 0
351. 
352. \# Redis swap文件分成了很多的page，一个对象可以保存在多个page上面，但一个page上不能被多个对象共享，vm-page-size是要根据存储的数据大小来设定的。
353. \# 建议如果存储很多小对象，page大小最后设置为32或64bytes；如果存储很大的对象，则可以使用更大的page，如果不确定，就使用默认值
354. vm-page-size 32
355. 
356. \# 设置swap文件中的page数量由于页表（一种表示页面空闲或使用的bitmap）是存放在内存中的，在磁盘上每8个pages将消耗1byte的内存
357. \# swap空间总容量为 vm-page-size \* vm-pages
358. \#
359. \# With the default of 32-bytes memory pages and 134217728 pages Redis will
360. \# use a 4 GB swap file, that will use 16 MB of RAM for the page table.
361. \#
362. \# It's better to use the smallest acceptable value for your application,
363. \# but the default is large in order to work in most conditions.
364. vm-pages 134217728
365. 
366. \# Max number of VM I/O threads running at the same time.
367. \# This threads are used to read/write data from/to swap file, since they
368. \# also encode and decode objects from disk to memory or the reverse, a bigger
369. \# number of threads can help with big objects even if they can't help with
370. \# I/O itself as the physical device may not be able to couple with many
371. \# reads/writes operations at the same time.
372. \# 设置访问swap文件的I/O线程数，最后不要超过机器的核数，如果设置为0，那么所有对swap文件的操作都是串行的，可能会造成比较长时间的延迟，默认值为4
373. vm-max-threads 4
374. 
375. \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\# ADVANCED CONFIG \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#
376. 
377. \# Hashes are encoded in a special way (much more memory efficient) when they
378. \# have at max a given numer of elements, and the biggest element does not
379. \# exceed a given threshold. You can configure this limits with the following
380. \# configuration directives.
381. \# 指定在超过一定的数量或者最大的元素超过某一临界值时，采用一种特殊的哈希算法
382. hash-max-zipmap-entries 512
383. hash-max-zipmap-value 64
384. 
385. \# Similarly to hashes, small lists are also encoded in a special way in order
386. \# to save a lot of space. The special representation is only used when
387. \# you are under the following limits:
388. list-max-ziplist-entries 512
389. list-max-ziplist-value 64
390. 
391. \# Sets have a special encoding in just one case: when a set is composed
392. \# of just strings that happens to be integers in radix 10 in the range
393. \# of 64 bit signed integers.
394. \# The following configuration setting sets the limit in the size of the
395. \# set in order to use this special memory saving encoding.
396. set-max-intset-entries 512
397. 
398. \# Similarly to hashes and lists, sorted sets are also specially encoded in
399. \# order to save a lot of space. This encoding is only used when the length and
400. \# elements of a sorted set are below the following limits:
401. zset-max-ziplist-entries 128
402. zset-max-ziplist-value 64
403. 
404. \# Active rehashing uses 1 millisecond every 100 milliseconds of CPU time in
405. \# order to help rehashing the main Redis hash table (the one mapping top-level
406. \# keys to values). The hash table implementation redis uses (see dict.c)
407. \# performs a lazy rehashing: the more operation you run into an hash table
408. \# that is rhashing, the more rehashing "steps" are performed, so if the
409. \# server is idle the rehashing is never complete and some more memory is used
410. \# by the hash table.
411. \#
412. \# The default is to use this millisecond 10 times every second in order to
413. \# active rehashing the main dictionaries, freeing memory when possible.
414. \#
415. \# If unsure:
416. \# use "activerehashing no" if you have hard latency requirements and it is
417. \# not a good thing in your environment that Redis can reply form time to time
418. \# to queries with 2 milliseconds delay.
419. \# 指定是否激活重置哈希，默认为开启
420. activerehashing yes
421. 
422. \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\# INCLUDES \#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#\#
423. 
424. \# 指定包含其他的配置文件，可以在同一主机上多个Redis实例之间使用同一份配置文件，而同时各实例又拥有自己的特定配置文件
425. \# include /path/to/local.conf
426. \# include /path/to/other.conf