官方2.6配置如下:
# Redis configuration file exampleNote on units: when memory size is needed,it is possible to specify
it in the usual form of 1k 5GB 4M and so forth:
1k => 1000 bytes
1kb => 1024 bytes
1m => 1000000 bytes
1mb => 1024*1024 bytes
1g => 1000000000 bytes
1gb => 102410241024 bytes
units are case insensitive so 1GB 1Gb 1gB are all the same.
By default Redis does not run as a daemon. Use 'yes' if you need it.
Note that Redis will write a pid file in /var/run/redis.pid when daemonized.
daemonize no
When running daemonized,Redis writes a pid file in /var/run/redis.pid by
default. You can specify a custom pid file location here.
pidfile /var/run/redis.pid
Accept connections on the specified port,default is 6379.
If port 0 is specified Redis will not listen on a TCP socket.
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
Close the connection after a client is idle for N seconds (0 to disable)
timeout 0
TCP keepalive.
If non-zero,use SO_KEEPALIVE to send TCP ACKs to clients in absence
of communication. This is useful for two reasons:
1) Detect dead peers.
2) Take the connection alive from the point of view of network
equipment in the middle.
On Linux,the specified value (in seconds) is the period used to send ACKs.
Note that to close the connection the double of the time is needed.
On other kernels the period depends on the kernel configuration.
A reasonable value for this option is 60 seconds.
tcp-keepalive 0
Specify the server verbosity level.
This can be one of:
debug (a lot of information,useful for development/testing)
verbose (many rarely useful info,but not a mess like the debug level)
notice (moderately verbose,what you want in production probably)
warning (only very important / critical messages are logged)
loglevel notice
Specify the log file name. Also 'stdout' can be used to force
Redis to log on the standard output. Note that if you use standard
output for logging but daemonize,logs will be sent to /dev/null
logfile stdout
To enable logging to the system logger,just set 'syslog-enabled' to yes,# and optionally update the other syslog parameters to suit your needs.
syslog-enabled no
Specify the syslog identity.
syslog-ident redis
Specify the syslog facility. Must be USER or between LOCAL0-LOCAL7.
syslog-facility local0
Set the number of databases. The default database is DB 0,you can select
a different one on a per-connection basis using SELECT
where dbid is a number between 0 and 'databases'-1
databases 16
################################ SNAPSHOTTING #################################
Save the DB on disk:
save
Will save the DB if both the given number of seconds and the given
number of write operations against the DB occurred.
In the example below the behavIoUr will be to save:
after 900 sec (15 min) if at least 1 key changed
after 300 sec (5 min) if at least 10 keys changed
after 60 sec if at least 10000 keys changed
Note: you can disable saving at all commenting all the "save" lines.
It is also possible to remove all the prevIoUsly configured save
points by adding a save directive with a single empty string argument
like in the following example:
save ""
save 900 1
save 300 10
save 60 10000By default Redis will stop accepting writes if RDB snapshots are enabled
(at least one save point) and the latest background save Failed.
This will make the user aware (in an hard way) that data is not persisting
on disk properly,otherwise chances are that no one will notice and some
distater will happen.
If the background saving process will start working again Redis will
automatically allow writes again.
However if you have setup your proper monitoring of the Redis server
and persistence,you may want to disable this feature so that Redis will
continue to work as usually even if there are problems with disk,# permissions,and so forth.
stop-writes-on-bgsave-error yes
Compress string objects using LZF when dump .rdb databases?
For default that's set to 'yes' as it's almost always a win.
If you want to save some cpu in the saving child set it to 'no' but
the dataset will likely be bigger if you have compressible values or keys.
rdbcompression yes
Since version 5 of RDB a CRC64 checksum is placed at the end of the file.
This makes the format more resistant to corruption but there is a performance
hit to pay (around 10%) when saving and loading RDB files,so you can disable it
for maximum performances.
RDB files created with checksum disabled have a checksum of zero that will
tell the loading code to skip the check.
rdbchecksum yes
The filename where to dump the DB
dbfilename dump.rdb
The working directory.
The DB will be written inside this directory,with the filename specified
above using the 'dbfilename' configuration directive.
The Append Only File will also be created inside this directory.
Note that you must specify a directory here,not a file name.
dir ./
################################# REPLICATION #################################
Master-Slave replication. Use slaveof to make a Redis instance a copy of
another Redis server. Note that the configuration is local to the slave
so for example it is possible to configure the slave to save the DB with a
different interval,or to listen to another port,and so on.
slaveof
If the master is password protected (using the "requirepass" configuration
directive below) it is possible to tell the slave to authenticate before
starting the replication synchronization process,otherwise the master will
refuse the slave request.
masterauth
When a slave loses its connection with the master,or when the replication
is still in progress,the slave can act in two different ways:
1) if slave-serve-stale-data is set to 'yes' (the default) the slave will
still reply to client requests,possibly with out of date data,or the
data set may just be empty if this is the first synchronization.
2) if slave-serve-stale-data is set to 'no' the slave will reply with
an error "SYNC with master in progress" to all the kind of commands
but to INFO and SLAVEOF.
slave-serve-stale-data yes
You can configure a slave instance to accept writes or not. Writing against
a slave instance may be useful to store some ephemeral data (because data
written on a slave will be easily deleted after resync with the master) but
may also cause problems if clients are writing to it because of a
misconfiguration.
Since Redis 2.6 by default slaves are read-only.
Note: read only slaves are not designed to be exposed to untrusted clients
on the internet. It's just a protection layer against misuse of the instance.
Still a read only slave exports by default all the administrative commands
such as CONFIG,DEBUG,and so forth. To a limited extend you can improve
security of read only slaves using 'rename-command' to shadow all the
administrative / dangerous commands.
slave-read-only yes
Slaves send PINGs to server in a predefined interval. It's possible to change
this interval with the repl_ping_slave_period option. The default value is 10
seconds.
repl-ping-slave-period 10
The following option sets a timeout for both Bulk transfer I/O timeout and
master data or ping response timeout. The default value is 60 seconds.
It is important to make sure that this value is greater than the value
specified for repl-ping-slave-period otherwise a timeout will be detected
every time there is low traffic between the master and the slave.
repl-timeout 60
Disable TCP_NODELAY on the slave socket after SYNC?
If you select "yes" Redis will use a smaller number of TCP packets and
less bandwidth to send data to slaves. But this can add a delay for
the data to appear on the slave side,up to 40 milliseconds with
Linux kernels using a default configuration.
If you select "no" the delay for data to appear on the slave side will
be reduced but more bandwidth will be used for replication.
By default we optimize for low latency,but in very high traffic conditions
or when the master and slaves are many hops away,turning this to "yes" may
be a good idea.
repl-disable-tcp-nodelay no
The slave priority is an integer number published by Redis in the INFO output.
It is used by Redis Sentinel in order to select a slave to promote into a
master if the master is no longer working correctly.
A slave with a low priority number is considered better for promotion,so
for instance if there are three slaves with priority 10,100,25 Sentinel will
pick the one wtih priority 10,that is the lowest.
However a special priority of 0 marks the slave as not able to perform the
role of master,so a slave with priority of 0 will never be selected by
Redis Sentinel for promotion.
By default the priority is 100.
slave-priority 100
################################## SECURITY ###################################
Require clients to issue AUTH
before processing any other commands. This might be useful in environments in which you do not trust
others with access to the host running redis-server.
This should stay commented out for backward compatibility and because most
people do not need auth (e.g. they run their own servers).
Warning: since Redis is pretty fast an outside user can try up to
150k passwords per second against a good Box. This means that you should
use a very strong password otherwise it will be very easy to break.
requirepass foobared
Command renaming.
It is possible to change the name of dangerous commands in a shared
environment. For instance the CONFIG command may be renamed into something
hard to guess so that it will still be available for internal-use tools
but not available for general clients.
Example:
rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52
It is also possible to completely kill a command by renaming it into
an empty string:
rename-command CONFIG ""
Please note that changing the name of commands that are logged into the
AOF file or transmitted to slaves may cause problems.
################################### LIMITS ####################################
Set the max number of connected clients at the same time. By default
this limit is set to 10000 clients,however if the Redis server is not
able to configure the process file limit to allow for the specified limit
the max number of allowed clients is set to the current file limit
minus 32 (as Redis reserves a few file descriptors for internal uses).
Once the limit is reached Redis will close all the new connections sending
an error 'max number of clients reached'.
maxclients 10000
Don't use more memory than the specified amount of bytes.
When the memory limit is reached Redis will try to remove keys
accordingly to the eviction policy selected (see maxmemmory-policy).
If Redis can't remove keys according to the policy,or if the policy is
set to 'noeviction',Redis will start to reply with errors to commands
that would use more memory,like SET,LPUSH,and so on,and will continue
to reply to read-only commands like GET.
This option is usually useful when using Redis as an LRU cache,or to set
an hard memory limit for an instance (using the 'noeviction' policy).
WARNING: If you have slaves attached to an instance with maxmemory on,# the size of the output buffers needed to Feed the slaves are subtracted
from the used memory count,so that network problems / resyncs will
not trigger a loop where keys are evicted,and in turn the output
buffer of slaves is full with DELs of keys evicted triggering the deletion
of more keys,and so forth until the database is completely emptied.
In short... if you have slaves attached it is suggested that you set a lower
limit for maxmemory so that there is some free RAM on the system for slave
output buffers (but this is not needed if the policy is 'noeviction').
maxmemory
MAXMEMORY POLICY: how Redis will select what to remove when maxmemory
is reached. You can select among five behaviors:
volatile-lru -> remove the key with an expire set using an LRU algorithm
allkeys-lru -> remove any key accordingly to the LRU algorithm
volatile-random -> remove a random key with an expire set
allkeys-random -> remove a random key,any key
volatile-ttl -> remove the key with the nearest expire time (minor TTL)
noeviction -> don't expire at all,just return an error on write operations
Note: with any of the above policies,Redis will return an error on write
operations,when there are not suitable keys for eviction.
At the date of writing this commands are: set setnx setex append
incr decr rpush lpush rpushx lpushx linsert lset rpoplpush sadd
sinter sinterstore sunion sunionstore sdiff sdiffstore zadd zincrby
zunionstore zinterstore hset hsetnx hmset hincrby incrby decrby
getset mset msetnx exec sort
The default is:
maxmemory-policy volatile-lru
LRU and minimal TTL algorithms are not precise algorithms but approximated
algorithms (in order to save memory),so you can select as well the sample
size to check. For instance for default Redis will check three keys and
pick the one that was used less recently,you can change the sample size
using the following configuration directive.
maxmemory-samples 3
############################## APPEND ONLY MODE ###############################
By default Redis asynchronously dumps the dataset on disk. This mode is
good enough in many applications,but an issue with the Redis process or
a power outage may result into a few minutes of writes lost (depending on
the configured save points).
The Append Only File is an alternative persistence mode that provides
much better durability. For instance using the default data fsync policy
(see later in the config file) Redis can lose just one second of writes in a
dramatic event like a server power outage,or a single write if something
wrong with the Redis process itself happens,but the operating system is
still running correctly.
AOF and RDB persistence can be enabled at the same time without problems.
If the AOF is enabled on startup Redis will load the AOF,that is the file
with the better durability guarantees.
Please check http://redis.io/topics/persistence for more information.
appendonly no
The name of the append only file (default: "appendonly.aof")
appendfilename appendonly.aof
The fsync() call tells the Operating System to actually write data on disk
instead to wait for more data in the output buffer. Some OS will really flush
data on disk,some other OS will just try to do it ASAP.
Redis supports three different modes:
no: don't fsync,just let the OS flush the data when it wants. Faster.
always: fsync after every write to the append only log . Slow,Safest.
everysec: fsync only one time every second. Compromise.
The default is "everysec",as that's usually the right compromise between
speed and data safety. It's up to you to understand if you can relax this to
"no" that will let the operating system flush the output buffer when
it wants,for better performances (but if you can live with the idea of
some data loss consider the default persistence mode that's snapshotting),# or on the contrary,use "always" that's very slow but a bit safer than
everysec.
More details please check the following article:
http://antirez.com/post/redis-persistence-demystified.html
If unsure,use "everysec".
appendfsync always
appendfsync everysec
appendfsync no
When the AOF fsync policy is set to always or everysec,and a background
saving process (a background save or AOF log background rewriting) is
performing a lot of I/O against the disk,in some Linux configurations
Redis may block too long on the fsync() call. Note that there is no fix for
this currently,as even performing fsync in a different thread will block
our synchronous write(2) call.
In order to mitigate this problem it's possible to use the following option
that will prevent fsync() from being called in the main process while a
BGSAVE or BGREWRITEAOF is in progress.
This means that while another child is saving,the durability of Redis is
the same as "appendfsync none". In practical terms,this means that it is
possible to lose up to 30 seconds of log in the worst scenario (with the
default Linux settings).
If you have latency problems turn this to "yes". Otherwise leave it as
"no" that is the safest pick from the point of view of durability.
no-appendfsync-on-rewrite no
Automatic rewrite of the append only file.
Redis is able to automatically rewrite the log file implicitly calling
BGREWRITEAOF when the AOF log size grows by the specified percentage.
This is how it works: Redis remembers the size of the AOF file after the
latest rewrite (if no rewrite has happened since the restart,the size of
the AOF at startup is used).
This base size is compared to the current size. If the current size is
bigger than the specified percentage,the rewrite is triggered. Also
you need to specify a minimal size for the AOF file to be rewritten,this
is useful to avoid rewriting the AOF file even if the percentage increase
is reached but it is still pretty small.
Specify a percentage of zero in order to disable the automatic AOF
rewrite feature.
auto-aof-rewrite-percentage 100
auto-aof-rewrite-min-size 64mb################################ LUA SCRIPTING ###############################
Max execution time of a Lua script in milliseconds.
If the maximum execution time is reached Redis will log that a script is
still in execution after the maximum allowed time and will start to
reply to queries with an error.
When a long running script exceed the maximum execution time only the
SCRIPT KILL and SHUTDOWN NOSAVE commands are available. The first can be
used to stop a script that did not yet called write commands. The second
is the only way to shut down the server in the case a write commands was
already issue by the script but the user don't want to wait for the natural
termination of the script.
Set it to 0 or a negative value for unlimited execution without warnings.
lua-time-limit 5000
################################## SLOW LOG ###################################
The Redis Slow Log is a system to log queries that exceeded a specified
execution time. The execution time does not include the I/O operations
like talking with the client,sending the reply and so forth,# but just the time needed to actually execute the command (this is the only
stage of command execution where the thread is blocked and can not serve
other requests in the meantime).
You can configure the slow log with two parameters: one tells Redis
what is the execution time,in microseconds,to exceed in order for the
command to get logged,and the other parameter is the length of the
slow log. When a new command is logged the oldest one is removed from the
queue of logged commands.
The following time is expressed in microseconds,so 1000000 is equivalent
to one second. Note that a negative number disables the slow log,while
a value of zero forces the logging of every command.
slowlog-log-slower-than 10000
There is no limit to this length. Just be aware that it will consume memory.
You can reclaim memory used by the slow log with SLOWLOG RESET.
slowlog-max-len 128
############################### ADVANCED CONFIG ###############################
Hashes are encoded using a memory efficient data structure when they have a
small number of entries,and the biggest entry does not exceed a given
threshold. These thresholds can be configured using the following directives.
hash-max-ziplist-entries 512
hash-max-ziplist-value 64Similarly 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 64Sets 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 64Active 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 rehashing,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
The client output buffer limits can be used to force disconnection of clients
that are not reading data from the server fast enough for some reason (a
common reason is that a Pub/Sub client can't consume messages as fast as the
publisher can produce them).
The limit can be set differently for the three different classes of clients:
normal -> normal clients
slave -> slave clients and MONITOR clients
pubsub -> clients subcribed to at least one pubsub channel or pattern
The Syntax of every client-output-buffer-limit directive is the following:
client-output-buffer-limit
A client is immediately disconnected once the hard limit is reached,or if
the soft limit is reached and remains reached for the specified number of
seconds (continuously).
So for instance if the hard limit is 32 megabytes and the soft limit is
16 megabytes / 10 seconds,the client will get disconnected immediately
if the size of the output buffers reach 32 megabytes,but will also get
disconnected if the client reaches 16 megabytes and continuously overcomes
the limit for 10 seconds.
By default normal clients are not limited because they don't receive data
without asking (in a push way),but just after a request,so only
asynchronous clients may create a scenario where data is requested faster
than it can read.
Instead there is a default limit for pubsub and slave clients,since
subscribers and slaves receive data in a push fashion.
Both the hard or the soft limit can be disabled by setting them to zero.
client-output-buffer-limit normal 0 0 0
client-output-buffer-limit slave 256mb 64mb 60
client-output-buffer-limit pubsub 32mb 8mb 60Redis calls an internal function to perform many background tasks,like
closing connections of clients in timeot,purging expired keys that are
never requested,and so forth.
Not all tasks are perforemd with the same frequency,but Redis checks for
tasks to perform accordingly to the specified "hz" value.
By default "hz" is set to 10. Raising the value will use more cpu when
Redis is idle,but at the same time will make Redis more responsive when
there are many keys expiring at the same time,and timeouts may be
handled with more precision.
The range is between 1 and 500,however a value over 100 is usually not
a good idea. Most users should use the default of 10 and raise this up to
100 only in environments where very low latency is required.
hz 10
When a child rewrites the AOF file,if the following option is enabled
the file will be fsync-ed every 32 MB of data generated. This is useful
in order to commit the file to the disk more incrementally and avoid
big latency spikes.
aof-rewrite-incremental-fsync 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