redis 配置说明

 

#是否以后台进程运行，默认为no，如果需要以后台进程运行则改为yes

daemonize no

#如果以后台进程运行的话，就需要指定pid，你可以在此自定义redis.pid文件的位置。

pidfile /var/run/redis.pid

#接受连接的端口号，如果端口是0则redis将不会监听TCP socket连接

port 6379

# If you want you can bind a single interface, if the bind option is not

# specified all the interfaces will listen for incoming connections.

#

# bind 127.0.0.1

# Specify the path for the unix socket that will be used to listen for

# incoming connections. There is no default, so Redis will not listen

# on a unix socket when not specified.

#

# unixsocket /tmp/redis.sock

# unixsocketperm 755

#连接超时时间，单位秒。(0 to disable)？

timeout 300000000

#日志级别，默认是verbose（详细），各种日志级别：

#debug:很详细的信息，适合开发和测试

#verbose:包含许多不太有用的信息，但比debug要清爽一些（many rarely useful info, but not a mess like #the debug level）

#notice:比较适合生产环境

#warning:警告信息

loglevel verbose

#指定log文件的名字，默认是stdout。stdout会让redis把日志输出到标准输出。但是如果使用stdout而又以后台进#程的方式运行redis，则日志会输出到/dev/null

logfile stdout

#'syslog-enabled'设置为yes会把日志输出到系统日志，默认是no

# syslog-enabled no

#指定syslog的标示符，如果'syslog-enabled'是no，则这个选项无效。

# syslog-ident redis

#指定syslog 设备（facility), 必须是USER或者LOCAL0到LOCAL7.

# syslog-facility local0

#设置数据库数目。默认的数据库是DB 0。可以通过SELECT <dbid>来选择一个数据库，dbid是[0,'databases'-1]的数字

databases 16

################## 快照#################################

# 硬盘上保存数据:

#   save <seconds> <changes>

#   <seconds>和<changes>都满足时就会触发数据保存动作。

#   以下面的例子来说明：

#   过了900秒并且有1个key发生了改变 就会触发save动作

#   过了300秒并且有10个key发生了改变 就会触发save动作

#   过了60秒并且至少有10000个key发生了改变 也会触发save动作

#   注意：如果你不想让redis自动保存数据，那就把下面的配置注释掉！

save 900 1

save 300 10

save 60 10000

#存储数据时是否压缩数据。默认是yes。

rdbcompression yes

# 保存dump数据的文件名

dbfilename dump.rdb

# 工作目录.

# 数据会被持久化到这个目录下的‘dbfilename’指定的文件中。

# 注意，这里指定的必须是目录而不能是文件。

dir ./

######## REPLICATION（复制，冗余）#################################

# Master-Slave replication. 使用slaveof把一个 Redis 实例设置成为另一个Redis server的从库（热备）. 注意： #配置只对当前slave有效。

# 因此可以把某个slave配置成使用不同的时间间隔来保存数据或者监听其他端口等等。

#命令格式：

# slaveof <masterip> <masterport>

#如果master有密码保护，则在slave与master进行数据同步之前需要进行密码校验，否则master会拒绝slave的请#求。

# masterauth <master-password>

#当slave丢失与master的连接时，或者slave仍然在于master进行数据同步时（还没有与master保持一致），#slave可以有两种方式来响应客户端请求：

# 1) 如果 slave-serve-stale-data 设置成 'yes' (the default) slave会仍然响应客户端请求,此时可能会有问题。

# 2) 如果 slave-serve-stale data设置成  'no'  slave会返回"SYNC with master in progress"这样的错误信息。 但 INFO 和SLAVEOF命令除外。

slave-serve-stale-data yes

############### 安全 ###################################

# 需要客户端在执行任何命令之前指定 AUTH <PASSWORD>

# requirepass foobared

# 命令重命名.

# 例如:

# rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52

# 同样可以通过把一个命令重命名为空串来彻底kill掉这个命令，比如：

# rename-command CONFIG ""

#################### 限制 ####################################

# 设置最大连接数. 默认没有限制,  '0' 意味着不限制.

# maxclients 128

#最大可使用内存。如果超过，Redis会试图删除EXPIRE集合中的keys，具体做法是：Redis会试图释放即将过期的#keys，而保护还有很长生命周期的keys。

#如果这样还不行，Redis就会报错，但像GET之类的查询请求还是会得到响应。

#警告：如果你想把Redis视为一个真正的DB的话，那不要设置<maxmemory>,只有你只想把Redis作为cache或者

#有状态的server（'state' server)时才需要设置。

# maxmemory <bytes>

#内存清理策略：如果达到了maxmemory，你可以采取如下动作：

# volatile-lru -> 使用LRU算法来删除过期的set

# allkeys-lru -> 删除任何遵循LRU算法的key

# volatile-random ->随机地删除过期set中的key

# allkeys->random -> 随机地删除一个key

# volatile-ttl -> 删除最近即将过期的key（the nearest expire time (minor TTL)）

# noeviction -> 根本不过期，写操作直接报错

# 默认策略:

# maxmemory-policy volatile-lru

# 对于处理redis内存来说，LRU和minor TTL算法不是精确的，而是近似的（估计的）算法。所以我们会检查某些样本#来达到内存检查的目的。默认的样本数是3，你可以修改它。

# maxmemory-samples 3

################# APPEND ONLY MODE ###############################

#默认情况下，Redis会异步的把数据保存到硬盘。如果你的应用场景允许因为系统崩溃等极端情 况而导致最新数据丢失#的话，那这种做法已经很ok了。否则你应该打开‘append only’模式，开启这种模式后，Redis会在#appendonly.aof文件中添加每一个写操作，这个文件会在Redis启动时被读取来在内存中 重新构建数据集。

#注意：如果你需要，你可以同时开启‘append only’模式和异步dumps模式（你需要注释掉上面的‘save’表达式来禁#止dumps），这种情况下，Redis重建数据集时会优先使用appendonly.aof而忽略dump.rdb

appendonly no

#  append only 文件名 (默认: "appendonly.aof")

# appendfilename appendonly.aof

# 调用fsync()函数通知操作系统立刻向硬盘写数据

# Redis支持3中模式:

# no:不fsync, 只是通知OS可以flush数据了，具体是否flush取决于OS.性能更好.

# always: 每次写入append only 日志文件后都会fsync . 性能差，但很安全.

# everysec: 没间隔1秒进行一次fsync. 折中.

# 默认是 "everysec"

# appendfsync always

appendfsync everysec

# appendfsync no

# 当AOF fsync策略被设置为always或者everysec并且后台保存进程（saving process)正在执行大量I/O操作时

# Redis可能会在fsync()调用上阻塞过长时间

no-appendfsync-on-rewrite no

# append only 文件的自动重写

# 当AOF 日志文件即将增长到指定百分比时，Redis可以通过调用BGREWRITEAOF 来自动重写append only文件。

# 它是这么干的：Redis会记住最近一次重写后的AOF 文件size。然后它会把这个size与当前size进行比较，如果当前# size比指定的百分比大，就会触发重写。同样，你需要指定AOF文件被重写的最小size，这对避免虽然百分比达到了# 但是实际上文件size还是很小（这种情况没有必要重写）却导致AOF文件重写的情况很有用。

# auto-aof-rewrite-percentage 设置为 0 可以关闭AOF重写功能

auto-aof-rewrite-percentage 100

auto-aof-rewrite-min-size 64mb

################## SLOW LOG ###################################

# Redis slow log用来记录超过指定执行时间的查询。

# 你可以指定两个参数：一个是慢查询的阀值，单位是毫秒；另外一个是slow log的长度，相当于一个队列。

# 负数则关闭slow log，0则会导致每个命令都被记录

slowlog-log-slower-than 10000

# 不设置会消耗过多内存，所以还是要设置一下。可以使用SLOWLOG RESET命令来回收slow log使用的内存

slowlog-max-len 1024

################ 虚拟内存 ###############################

#使用redis 就别用虚拟内存了，绝对不是一个好主意，加个机器吧，所以这里不翻译啦！！

### WARNING! Virtual Memory is deprecated in Redis 2.4

### The use of Virtual Memory is strongly discouraged.

# Virtual Memory allows Redis to work with datasets bigger than the actual

# amount of RAM needed to hold the whole dataset in memory.

# In order to do so very used keys are taken in memory while the other keys

# are swapped into a swap file, similarly to what operating systems do

# with memory pages.

# To enable VM just set 'vm-enabled' to yes, and set the following three

# VM parameters accordingly to your needs.

vm-enabled no

# vm-enabled yes

# This is the path of the Redis swap file. As you can guess, swap files

# can't be shared by different Redis instances, so make sure to use a swap

# file for every redis process you are running. Redis will complain if the

# swap file is already in use.

# The best kind of storage for the Redis swap file (that's accessed at random) 

# is a Solid State Disk (SSD).

# *** WARNING *** if you are using a shared hosting the default of putting

# the swap file under /tmp is not secure. Create a dir with access granted

# only to Redis user and configure Redis to create the swap file there.

vm-swap-file /tmp/redis.swap

# vm-max-memory configures the VM to use at max the specified amount of

# RAM. Everything that deos not fit will be swapped on disk *if* possible, that

# is, if there is still enough contiguous space in the swap file.

# With vm-max-memory 0 the system will swap everything it can. Not a good

# default, just specify the max amount of RAM you can in bytes, but it's

# better to leave some margin. For instance specify an amount of RAM

# that's more or less between 60 and 80% of your free RAM.

vm-max-memory 0

# Redis swap files is split into pages. An object can be saved using multiple

# contiguous pages, but pages can't be shared between different objects.

# So if your page is too big, small objects swapped out on disk will waste

# a lot of space. If you page is too small, there is less space in the swap

# file (assuming you configured the same number of total swap file pages).

# If you use a lot of small objects, use a page size of 64 or 32 bytes.

# If you use a lot of big objects, use a bigger page size.

# If unsure, use the default :)

vm-page-size 32

# Number of total memory pages in the swap file.

# Given that the page table (a bitmap of free/used pages) is taken in memory,

# every 8 pages on disk will consume 1 byte of RAM.

# The total swap size is vm-page-size * vm-pages

# With the default of 32-bytes memory pages and 134217728 pages Redis will

# use a 4 GB swap file, that will use 16 MB of RAM for the page table.

# It's better to use the smallest acceptable value for your application,

# but the default is large in order to work in most conditions.

vm-pages 134217728

 

# Max number of VM I/O threads running at the same time.

# This threads are used to read/write data from/to swap file, since they

# also encode and decode objects from disk to memory or the reverse, a bigger

# number of threads can help with big objects even if they can't help with

# I/O itself as the physical device may not be able to couple with many

# reads/writes operations at the same time.

# The special value of 0 turn off threaded I/O and enables the blocking

# Virtual Memory implementation.

vm-max-threads 4

################高级配置###############################

# Hashes are encoded in a special way (much more memory efficient) when they

# have at max a given numer of elements, and the biggest element does not

# exceed a given threshold. You can configure this limits with the following

# configuration directives.

hash-max-zipmap-entries 512

hash-max-zipmap-value 64

# Similarly to hashes, small lists are also encoded in a special way in order

# to save a lot of space. The special representation is only used when

# you are under the following limits:

list-max-ziplist-entries 512

list-max-ziplist-value 64

# Sets have a special encoding in just one case: when a set is composed

# of just strings that happens to be integers in radix 10 in the range

# of 64 bit signed integers.

# The following configuration setting sets the limit in the size of the

# set in order to use this special memory saving encoding.

set-max-intset-entries 512

# Similarly to hashes and lists, sorted sets are also specially encoded in

# order to save a lot of space. This encoding is only used when the length and

# elements of a sorted set are below the following limits:

zset-max-ziplist-entries 128

zset-max-ziplist-value 64

# Active rehashing uses 1 millisecond every 100 milliseconds of CPU time in

# order to help rehashing the main Redis hash table (the one mapping top-level

# keys to values). The hash table implementation redis uses (see dict.c)

# performs a lazy rehashing: the more operation you run into an hash table

# that is rhashing, the more rehashing "steps" are performed, so if the

# server is idle the rehashing is never complete and some more memory is used

# by the hash table.

# The default is to use this millisecond 10 times every second in order to

# active rehashing the main dictionaries, freeing memory when possible.

# If unsure:

# use "activerehashing no" if you have hard latency requirements and it is

# not a good thing in your environment that Redis can reply form time to time

# to queries with 2 milliseconds delay.

# use "activerehashing yes" if you don't have such hard requirements but

# want to free memory asap when possible.

activerehashing yes

################## INCLUDES ###################################

# Include one or more other config files here.  This is useful if you

# have a standard template that goes to all redis server but also need

# to customize a few per-server settings.  Include files can include

# other files, so use this wisely.

# include /path/to/local.conf

# include /path/to/other.conf