redis配置文件内容讲解

# Redis configuration file example.

#

# Note that in order to read the configuration file, Redis must be

# started with the file path as first argument:

#

# ./redis-server /path/to/redis.conf

# Note on units: when memory size is needed, it is possible to specify

# it in the usual form of 1k 5GB 4M and so forth:

# ---------------redis中一些单位的设置方式，redis只支持字节（byte），不支持其他类型，大小写不敏感-------

# 1k => 1000 bytes

# 1kb => 1024 bytes

# 1m => 1000000 bytes

# 1mb => 1024*1024 bytes

# 1g => 1000000000 bytes

# 1gb => 1024*1024*1024 bytes

#

# units are case insensitive so 1GB 1Gb 1gB are all the same.

################################## INCLUDES （包含文件）###################################

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

# have a standard template that goes to all Redis servers but also need

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

# other files, so use this wisely.

#

# Note that option "include" won't be rewritten by command "CONFIG REWRITE"

# from admin or Redis Sentinel. Since Redis always uses the last processed

# line as value of a configuration directive, you'd better put includes

# at the beginning of this file to avoid overwriting config change at runtime.

#

# If instead you are interested in using includes to override configuration

# options, it is better to use include as the last line.

#

# Included paths may contain wildcards. All files matching the wildcards will

# be included in alphabetical order.

# Note that if an include path contains a wildcards but no files match it when

# the server is started, the include statement will be ignored and no error will

# be emitted. It is safe, therefore, to include wildcard files from empty

# directories.

#

# include /path/to/local.conf

# include /path/to/other.conf

# include /path/to/fragments/*.conf

#

################################## MODULES #####################################

# Load modules at startup. If the server is not able to load modules

# it will abort. It is possible to use multiple loadmodule directives.

#

# loadmodule /path/to/my_module.so

# loadmodule /path/to/other_module.so

################################## NETWORK（网络部分配置） #####################################

# By default, if no "bind" configuration directive is specified, Redis listens

# for connections from all available network interfaces on the host machine.

# It is possible to listen to just one or multiple selected interfaces using

# the "bind" configuration directive, followed by one or more IP addresses.

# Each address can be prefixed by "-", which means that redis will not fail to

# start if the address is not available. Being not available only refers to

# addresses that does not correspond to any network interface. Addresses that

# are already in use will always fail, and unsupported protocols will always BE

# silently skipped.

#

# Examples:

#

# bind 192.168.1.100 10.0.0.1 # listens on two specific IPv4 addresses

# --------------如果打开下面内容的注释，redis则只能本地连接，不能远程连接-------------

# bind 127.0.0.1 ::1 # listens on loopback IPv4 and IPv6

# bind * -::* # like the default, all available interfaces

#

# ~~~ WARNING ~~~ If the computer running Redis is directly exposed to the

# internet, binding to all the interfaces is dangerous and will expose the

# instance to everybody on the internet. So by default we uncomment the

# following bind directive, that will force Redis to listen only on the

# IPv4 and IPv6 (if available) loopback interface addresses (this means Redis

# will only be able to accept client connections from the same host that it is

# running on).

#

# IF YOU ARE SURE YOU WANT YOUR INSTANCE TO LISTEN TO ALL THE INTERFACES

# COMMENT OUT THE FOLLOWING LINE.

#

# You will also need to set a password unless you explicitly disable protected

# mode.

# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

#bind 127.0.0.1 -::1

# By default, outgoing connections (from replica to master, from Sentinel to

# instances, cluster bus, etc.) are not bound to a specific local address. In

# most cases, this means the operating system will handle that based on routing

# and the interface through which the connection goes out.

#

# Using bind-source-addr it is possible to configure a specific address to bind

# to, which may also affect how the connection gets routed.

#

# Example:

#

# bind-source-addr 10.0.0.1

# Protected mode is a layer of security protection, in order to avoid that

# Redis instances left open on the internet are accessed and exploited.

#

# When protected mode is on and the default user has no password, the server

# only accepts local connections from the IPv4 address (127.0.0.1), IPv6 address

# (::1) or Unix domain sockets.

#

# By default protected mode is enabled. You should disable it only if

# you are sure you want clients from other hosts to connect to Redis

# even if no authentication is configured.

#--------------------------------是否支持远程访问，默认是no即不支持--------------------------

protected-mode no

# Redis uses default hardened security configuration directives to reduce the

# attack surface on innocent users. Therefore, several sensitive configuration

# directives are immutable, and some potentially-dangerous commands are blocked.

#

# Configuration directives that control files that Redis writes to (e.g., 'dir'

# and 'dbfilename') and that aren't usually modified during runtime

# are protected by making them immutable.

#

# Commands that can increase the attack surface of Redis and that aren't usually

# called by users are blocked by default.

#

# These can be exposed to either all connections or just local ones by setting

# each of the configs listed below to either of these values:

#

# no - Block for any connection (remain immutable)

# yes - Allow for any connection (no protection)

# local - Allow only for local connections. Ones originating from the

# IPv4 address (127.0.0.1), IPv6 address (::1) or Unix domain sockets.

#

# enable-protected-configs no

# enable-debug-command no

# enable-module-command no

# Accept connections on the specified port, default is 6379 (IANA #815344).

# If port 0 is specified Redis will not listen on a TCP socket.

#-----------------端口号（默认是6379，可以改成其他的）--------------------------------------

port 6379

# TCP listen() backlog.

#

# In high requests-per-second environments you need a high backlog in order

# to avoid slow clients connection issues. Note that the Linux kernel

# will silently truncate it to the value of /proc/sys/net/core/somaxconn so

# make sure to raise both the value of somaxconn and tcp_max_syn_backlog

# in order to get the desired effect.

tcp-backlog 511

# Unix socket.

#

# 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 /run/redis.sock

# unixsocketperm 700

# Close the connection after a client is idle for N seconds (0 to disable)

#-----------------连接超时时间，如果是0则永不超时------------------------

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) Force network equipment in the middle to consider the connection to be

# alive.

#

# 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 300 seconds, which is the new

# Redis default starting with Redis 3.2.1.

#-----------检查心跳，即每间隔300检查服务是否有人操作，如果无人操作，则断开连接--------------

tcp-keepalive 300

# Apply OS-specific mechanism to mark the listening socket with the specified

# ID, to support advanced routing and filtering capabilities.

#

# On Linux, the ID represents a connection mark.

# On FreeBSD, the ID represents a socket cookie ID.

# On OpenBSD, the ID represents a route table ID.

#

# The default value is 0, which implies no marking is required.

# socket-mark-id 0

################################# TLS/SSL #####################################

# By default, TLS/SSL is disabled. To enable it, the "tls-port" configuration

# directive can be used to define TLS-listening ports. To enable TLS on the

# default port, use:

#

# port 0

# tls-port 6379

# Configure a X.509 certificate and private key to use for authenticating the

# server to connected clients, masters or cluster peers. These files should be

# PEM formatted.

#

# tls-cert-file redis.crt

# tls-key-file redis.key

#

# If the key file is encrypted using a passphrase, it can be included here

# as well.

#

# tls-key-file-pass secret

# Normally Redis uses the same certificate for both server functions (accepting

# connections) and client functions (replicating from a master, establishing

# cluster bus connections, etc.).

#

# Sometimes certificates are issued with attributes that designate them as

# client-only or server-only certificates. In that case it may be desired to use

# different certificates for incoming (server) and outgoing (client)

# connections. To do that, use the following directives:

#

# tls-client-cert-file client.crt

# tls-client-key-file client.key

#

# If the key file is encrypted using a passphrase, it can be included here

# as well.

#

# tls-client-key-file-pass secret

# Configure a DH parameters file to enable Diffie-Hellman (DH) key exchange,

# required by older versions of OpenSSL (<3.0). Newer versions do not require

# this configuration and recommend against it.

#

# tls-dh-params-file redis.dh

# Configure a CA certificate(s) bundle or directory to authenticate TLS/SSL

# clients and peers. Redis requires an explicit configuration of at least one

# of these, and will not implicitly use the system wide configuration.

#

# tls-ca-cert-file ca.crt

# tls-ca-cert-dir /etc/ssl/certs

# By default, clients (including replica servers) on a TLS port are required

# to authenticate using valid client side certificates.

#

# If "no" is specified, client certificates are not required and not accepted.

# If "optional" is specified, client certificates are accepted and must be

# valid if provided, but are not required.

#

# tls-auth-clients no

# tls-auth-clients optional

# By default, a Redis replica does not attempt to establish a TLS connection

# with its master.

#

# Use the following directive to enable TLS on replication links.

#

# tls-replication yes

# By default, the Redis Cluster bus uses a plain TCP connection. To enable

# TLS for the bus protocol, use the following directive:

#

# tls-cluster yes

# By default, only TLSv1.2 and TLSv1.3 are enabled and it is highly recommended

# that older formally deprecated versions are kept disabled to reduce the attack surface.

# You can explicitly specify TLS versions to support.

# Allowed values are case insensitive and include "TLSv1", "TLSv1.1", "TLSv1.2",

# "TLSv1.3" (OpenSSL >= 1.1.1) or any combination.

# To enable only TLSv1.2 and TLSv1.3, use:

#

# tls-protocols "TLSv1.2 TLSv1.3"

# Configure allowed ciphers. See the ciphers(1ssl) manpage for more information

# about the syntax of this string.

#

# Note: this configuration applies only to <= TLSv1.2.

#

# tls-ciphers DEFAULT:!MEDIUM

# Configure allowed TLSv1.3 ciphersuites. See the ciphers(1ssl) manpage for more

# information about the syntax of this string, and specifically for TLSv1.3

# ciphersuites.

#

# tls-ciphersuites TLS_CHACHA20_POLY1305_SHA256

# When choosing a cipher, use the server's preference instead of the client

# preference. By default, the server follows the client's preference.

#

# tls-prefer-server-ciphers yes

# By default, TLS session caching is enabled to allow faster and less expensive

# reconnections by clients that support it. Use the following directive to disable

# caching.

#

# tls-session-caching no

# Change the default number of TLS sessions cached. A zero value sets the cache

# to unlimited size. The default size is 20480.

#

# tls-session-cache-size 5000

# Change the default timeout of cached TLS sessions. The default timeout is 300

# seconds.

#

# tls-session-cache-timeout 60

################################# GENERAL #####################################

# 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.

# When Redis is supervised by upstart or systemd, this parameter has no impact.

#--------------------------redis后台启动配置------------------------------

daemonize yes

# If you run Redis from upstart or systemd, Redis can interact with your

# supervision tree. Options:

# supervised no - no supervision interaction

# supervised upstart - signal upstart by putting Redis into SIGSTOP mode

# requires "expect stop" in your upstart job config

# supervised systemd - signal systemd by writing READY=1 to $NOTIFY_SOCKET

# on startup, and updating Redis status on a regular

# basis.

# supervised auto - detect upstart or systemd method based on

# UPSTART_JOB or NOTIFY_SOCKET environment variables

# Note: these supervision methods only signal "process is ready."

# They do not enable continuous pings back to your supervisor.

#

# The default is "no". To run under upstart/systemd, you can simply uncomment

# the line below:

#

# supervised auto

# If a pid file is specified, Redis writes it where specified at startup

# and removes it at exit.

#

# When the server runs non daemonized, no pid file is created if none is

# specified in the configuration. When the server is daemonized, the pid file

# is used even if not specified, defaulting to "/var/run/redis.pid".

#

# Creating a pid file is best effort: if Redis is not able to create it

# nothing bad happens, the server will start and run normally.

#

# Note that on modern Linux systems "/run/redis.pid" is more conforming

# and should be used instead.

#--------------redis启动的进程号，每次启动都会保存一个进程号在下列的文件中----------------

pidfile /var/run/redis_6379.pid

# 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)

#------------redis日志级别,上面是四个级别及其对应解释，默认是notice即生产级别。-----------------------------------------

loglevel notice

# Specify the log file name. Also the empty string 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

#--------------设置日志文件保存路径，默认为空------------------------

logfile ""

# 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

# To disable the built in crash log, which will possibly produce cleaner core

# dumps when they are needed, uncomment the following:

#

# crash-log-enabled no

# To disable the fast memory check that's run as part of the crash log, which

# will possibly let redis terminate sooner, uncomment the following:

#

# crash-memcheck-enabled no

# 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

#--------------------redis库，默认是有16个库-----------------------------

databases 16

# By default Redis shows an ASCII art logo only when started to log to the

# standard output and if the standard output is a TTY and syslog logging is

# disabled. Basically this means that normally a logo is displayed only in

# interactive sessions.

#

# However it is possible to force the pre-4.0 behavior and always show a

# ASCII art logo in startup logs by setting the following option to yes.

always-show-logo no

# By default, Redis modifies the process title (as seen in 'top' and 'ps') to

# provide some runtime information. It is possible to disable this and leave

# the process name as executed by setting the following to no.

set-proc-title yes

# When changing the process title, Redis uses the following template to construct

# the modified title.

#

# Template variables are specified in curly brackets. The following variables are

# supported:

#

# {title} Name of process as executed if parent, or type of child process.

# {listen-addr} Bind address or '*' followed by TCP or TLS port listening on, or

# Unix socket if only that's available.

# {server-mode} Special mode, i.e. "[sentinel]" or "[cluster]".

# {port} TCP port listening on, or 0.

# {tls-port} TLS port listening on, or 0.

# {unixsocket} Unix domain socket listening on, or "".

# {config-file} Name of configuration file used.

#

proc-title-template "{title} {listen-addr} {server-mode}"

################################ SNAPSHOTTING ################################

# Save the DB to disk.

#

# save [ ...]

#

# Redis will save the DB if the given number of seconds elapsed and it

# surpassed the given number of write operations against the DB.

#

# Snapshotting can be completely disabled with a single empty string argument

# as in following example:

#

# save ""

#

# Unless specified otherwise, by default Redis will save the DB:

# * After 3600 seconds (an hour) if at least 1 change was performed

# * After 300 seconds (5 minutes) if at least 100 changes were performed

# * After 60 seconds if at least 10000 changes were performed

#

# You can set these explicitly by uncommenting the following line.

#

# save 3600 1 300 100 60 10000

# By 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 a hard way) that data is not persisting

# on disk properly, otherwise chances are that no one will notice and some

# disaster 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 usual 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?

# By default compression is enabled 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

# Enables or disables full sanitization checks for ziplist and listpack etc when

# loading an RDB or RESTORE payload. This reduces the chances of a assertion or

# crash later on while processing commands.

# Options:

# no - Never perform full sanitization

# yes - Always perform full sanitization

# clients - Perform full sanitization only for user connections.

# Excludes: RDB files, RESTORE commands received from the master

# connection, and client connections which have the

# skip-sanitize-payload ACL flag.

# The default should be 'clients' but since it currently affects cluster

# resharding via MIGRATE, it is temporarily set to 'no' by default.

#

# sanitize-dump-payload no

# The filename where to dump the DB

dbfilename dump.rdb

# Remove RDB files used by replication in instances without persistence

# enabled. By default this option is disabled, however there are environments

# where for regulations or other security concerns, RDB files persisted on

# disk by masters in order to feed replicas, or stored on disk by replicas

# in order to load them for the initial synchronization, should be deleted

# ASAP. Note that this option ONLY WORKS in instances that have both AOF

# and RDB persistence disabled, otherwise is completely ignored.

#

# An alternative (and sometimes better) way to obtain the same effect is

# to use diskless replication on both master and replicas instances. However

# in the case of replicas, diskless is not always an option.

rdb-del-sync-files no

# 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-Replica replication. Use replicaof to make a Redis instance a copy of

# another Redis server. A few things to understand ASAP about Redis replication.

#

# +------------------+ +---------------+

# | Master | ---> | Replica |

# | (receive writes) | | (exact copy) |

# +------------------+ +---------------+

#

# 1) Redis replication is asynchronous, but you can configure a master to

# stop accepting writes if it appears to be not connected with at least

# a given number of replicas.

# 2) Redis replicas are able to perform a partial resynchronization with the

# master if the replication link is lost for a relatively small amount of

# time. You may want to configure the replication backlog size (see the next

# sections of this file) with a sensible value depending on your needs.

# 3) Replication is automatic and does not need user intervention. After a

# network partition replicas automatically try to reconnect to masters

# and resynchronize with them.

#

# replicaof

# If the master is password protected (using the "requirepass" configuration

# directive below) it is possible to tell the replica to authenticate before

# starting the replication synchronization process, otherwise the master will

# refuse the replica request.

#

# masterauth

#

# However this is not enough if you are using Redis ACLs (for Redis version

# 6 or greater), and the default user is not capable of running the PSYNC

# command and/or other commands needed for replication. In this case it's

# better to configure a special user to use with replication, and specify the

# masteruser configuration as such:

#

# masteruser

#

# When masteruser is specified, the replica will authenticate against its

# master using the new AUTH form: AUTH .

# When a replica loses its connection with the master, or when the replication

# is still in progress, the replica can act in two different ways:

#

# 1) if replica-serve-stale-data is set to 'yes' (the default) the replica 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 replica-serve-stale-data is set to 'no' the replica will reply with error

# "MASTERDOWN Link with MASTER is down and replica-serve-stale-data is set to 'no'"

# to all data access commands, excluding commands such as:

# INFO, REPLICAOF, AUTH, SHUTDOWN, REPLCONF, ROLE, CONFIG, SUBSCRIBE,

# UNSUBSCRIBE, PSUBSCRIBE, PUNSUBSCRIBE, PUBLISH, PUBSUB, COMMAND, POST,

# HOST and LATENCY.

#

replica-serve-stale-data yes

# You can configure a replica instance to accept writes or not. Writing against

# a replica instance may be useful to store some ephemeral data (because data

# written on a replica 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 replicas are read-only.

#

# Note: read only replicas 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 replica exports by default all the administrative commands

# such as CONFIG, DEBUG, and so forth. To a limited extent you can improve

# security of read only replicas using 'rename-command' to shadow all the

# administrative / dangerous commands.

replica-read-only yes

# Replication SYNC strategy: disk or socket.

#

# New replicas and reconnecting replicas that are not able to continue the

# replication process just receiving differences, need to do what is called a

# "full synchronization". An RDB file is transmitted from the master to the

# replicas.

#

# The transmission can happen in two different ways:

#

# 1) Disk-backed: The Redis master creates a new process that writes the RDB

# file on disk. Later the file is transferred by the parent

# process to the replicas incrementally.

# 2) Diskless: The Redis master creates a new process that directly writes the

# RDB file to replica sockets, without touching the disk at all.

#

# With disk-backed replication, while the RDB file is generated, more replicas

# can be queued and served with the RDB file as soon as the current child

# producing the RDB file finishes its work. With diskless replication instead

# once the transfer starts, new replicas arriving will be queued and a new

# transfer will start when the current one terminates.

#

# When diskless replication is used, the master waits a configurable amount of

# time (in seconds) before starting the transfer in the hope that multiple

# replicas will arrive and the transfer can be parallelized.

#

# With slow disks and fast (large bandwidth) networks, diskless replication

# works better.

repl-diskless-sync yes

# When diskless replication is enabled, it is possible to configure the delay

# the server waits in order to spawn the child that transfers the RDB via socket

# to the replicas.

#

# This is important since once the transfer starts, it is not possible to serve

# new replicas arriving, that will be queued for the next RDB transfer, so the

# server waits a delay in order to let more replicas arrive.

#

# The delay is specified in seconds, and by default is 5 seconds. To disable

# it entirely just set it to 0 seconds and the transfer will start ASAP.

repl-diskless-sync-delay 5

# When diskless replication is enabled with a delay, it is possible to let

# the replication start before the maximum delay is reached if the maximum

# number of replicas expected have connected. Default of 0 means that the

# maximum is not defined and Redis will wait the full delay.

repl-diskless-sync-max-replicas 0

# -----------------------------------------------------------------------------

# WARNING: RDB diskless load is experimental. Since in this setup the replica

# does not immediately store an RDB on disk, it may cause data loss during

# failovers. RDB diskless load + Redis modules not handling I/O reads may also

# cause Redis to abort in case of I/O errors during the initial synchronization

# stage with the master. Use only if you know what you are doing.

# -----------------------------------------------------------------------------

#

# Replica can load the RDB it reads from the replication link directly from the

# socket, or store the RDB to a file and read that file after it was completely

# received from the master.

#

# In many cases the disk is slower than the network, and storing and loading

# the RDB file may increase replication time (and even increase the master's

# Copy on Write memory and replica buffers).

# However, parsing the RDB file directly from the socket may mean that we have

# to flush the contents of the current database before the full rdb was

# received. For this reason we have the following options:

#

# "disabled" - Don't use diskless load (store the rdb file to the disk first)

# "on-empty-db" - Use diskless load only when it is completely safe.

# "swapdb" - Keep current db contents in RAM while parsing the data directly

# from the socket. Replicas in this mode can keep serving current

# data set while replication is in progress, except for cases where

# they can't recognize master as having a data set from same

# replication history.

# Note that this requires sufficient memory, if you don't have it,

# you risk an OOM kill.

repl-diskless-load disabled

# Master send PINGs to its replicas in a predefined interval. It's possible to

# change this interval with the repl_ping_replica_period option. The default

# value is 10 seconds.

#

# repl-ping-replica-period 10

# The following option sets the replication timeout for:

#

# 1) Bulk transfer I/O during SYNC, from the point of view of replica.

# 2) Master timeout from the point of view of replicas (data, pings).

# 3) Replica timeout from the point of view of masters (REPLCONF ACK pings).

#

# It is important to make sure that this value is greater than the value

# specified for repl-ping-replica-period otherwise a timeout will be detected

# every time there is low traffic between the master and the replica. The default

# value is 60 seconds.

#

# repl-timeout 60

# Disable TCP_NODELAY on the replica socket after SYNC?

#

# If you select "yes" Redis will use a smaller number of TCP packets and

# less bandwidth to send data to replicas. But this can add a delay for

# the data to appear on the replica side, up to 40 milliseconds with

# Linux kernels using a default configuration.

#

# If you select "no" the delay for data to appear on the replica 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 replicas are many hops away, turning this to "yes" may

# be a good idea.

repl-disable-tcp-nodelay no

# Set the replication backlog size. The backlog is a buffer that accumulates

# replica data when replicas are disconnected for some time, so that when a

# replica wants to reconnect again, often a full resync is not needed, but a

# partial resync is enough, just passing the portion of data the replica

# missed while disconnected.

#

# The bigger the replication backlog, the longer the replica can endure the

# disconnect and later be able to perform a partial resynchronization.

#

# The backlog is only allocated if there is at least one replica connected.

#

# repl-backlog-size 1mb

# After a master has no connected replicas for some time, the backlog will be

# freed. The following option configures the amount of seconds that need to

# elapse, starting from the time the last replica disconnected, for the backlog

# buffer to be freed.

#

# Note that replicas never free the backlog for timeout, since they may be

# promoted to masters later, and should be able to correctly "partially

# resynchronize" with other replicas: hence they should always accumulate backlog.

#

# A value of 0 means to never release the backlog.

#

# repl-backlog-ttl 3600

# The replica priority is an integer number published by Redis in the INFO

# output. It is used by Redis Sentinel in order to select a replica to promote

# into a master if the master is no longer working correctly.

#

# A replica with a low priority number is considered better for promotion, so

# for instance if there are three replicas with priority 10, 100, 25 Sentinel

# will pick the one with priority 10, that is the lowest.

#

# However a special priority of 0 marks the replica as not able to perform the

# role of master, so a replica with priority of 0 will never be selected by

# Redis Sentinel for promotion.

#

# By default the priority is 100.

replica-priority 100

# The propagation error behavior controls how Redis will behave when it is

# unable to handle a command being processed in the replication stream from a master

# or processed while reading from an AOF file. Errors that occur during propagation

# are unexpected, and can cause data inconsistency. However, there are edge cases

# in earlier versions of Redis where it was possible for the server to replicate or persist

# commands that would fail on future versions. For this reason the default behavior

# is to ignore such errors and continue processing commands.

#

# If an application wants to ensure there is no data divergence, this configuration

# should be set to 'panic' instead. The value can also be set to 'panic-on-replicas'

# to only panic when a replica encounters an error on the replication stream. One of

# these two panic values will become the default value in the future once there are

# sufficient safety mechanisms in place to prevent false positive crashes.

#

# propagation-error-behavior ignore

# Replica ignore disk write errors controls the behavior of a replica when it is

# unable to persist a write command received from its master to disk. By default,

# this configuration is set to 'no' and will crash the replica in this condition.

# It is not recommended to change this default, however in order to be compatible

# with older versions of Redis this config can be toggled to 'yes' which will just

# log a warning and execute the write command it got from the master.

#

# replica-ignore-disk-write-errors no

# -----------------------------------------------------------------------------

# By default, Redis Sentinel includes all replicas in its reports. A replica

# can be excluded from Redis Sentinel's announcements. An unannounced replica

# will be ignored by the 'sentinel replicas ' command and won't be

# exposed to Redis Sentinel's clients.

#

# This option does not change the behavior of replica-priority. Even with

# replica-announced set to 'no', the replica can be promoted to master. To

# prevent this behavior, set replica-priority to 0.

#

# replica-announced yes

# It is possible for a master to stop accepting writes if there are less than

# N replicas connected, having a lag less or equal than M seconds.

#

# The N replicas need to be in "online" state.

#

# The lag in seconds, that must be <= the specified value, is calculated from

# the last ping received from the replica, that is usually sent every second.

#

# This option does not GUARANTEE that N replicas will accept the write, but

# will limit the window of exposure for lost writes in case not enough replicas

# are available, to the specified number of seconds.

#

# For example to require at least 3 replicas with a lag <= 10 seconds use:

#

# min-replicas-to-write 3

# min-replicas-max-lag 10

#

# Setting one or the other to 0 disables the feature.

#

# By default min-replicas-to-write is set to 0 (feature disabled) and

# min-replicas-max-lag is set to 10.

# A Redis master is able to list the address and port of the attached

# replicas in different ways. For example the "INFO replication" section

# offers this information, which is used, among other tools, by

# Redis Sentinel in order to discover replica instances.

# Another place where this info is available is in the output of the

# "ROLE" command of a master.

#

# The listed IP address and port normally reported by a replica is

# obtained in the following way:

#

# IP: The address is auto detected by checking the peer address

# of the socket used by the replica to connect with the master.

#

# Port: The port is communicated by the replica during the replication

# handshake, and is normally the port that the replica is using to

# listen for connections.

#

# However when port forwarding or Network Address Translation (NAT) is

# used, the replica may actually be reachable via different IP and port

# pairs. The following two options can be used by a replica in order to

# report to its master a specific set of IP and port, so that both INFO

# and ROLE will report those values.

#

# There is no need to use both the options if you need to override just

# the port or the IP address.

#

# replica-announce-ip 5.5.5.5

# replica-announce-port 1234

############################### KEYS TRACKING #################################

# Redis implements server assisted support for client side caching of values.

# This is implemented using an invalidation table that remembers, using

# a radix key indexed by key name, what clients have which keys. In turn

# this is used in order to send invalidation messages to clients. Please

# check this page to understand more about the feature:

#

# https://redis.io/topics/client-side-caching

#

# When tracking is enabled for a client, all the read only queries are assumed

# to be cached: this will force Redis to store information in the invalidation

# table. When keys are modified, such information is flushed away, and

# invalidation messages are sent to the clients. However if the workload is

# heavily dominated by reads, Redis could use more and more memory in order

# to track the keys fetched by many clients.

#

# For this reason it is possible to configure a maximum fill value for the

# invalidation table. By default it is set to 1M of keys, and once this limit

# is reached, Redis will start to evict keys in the invalidation table

# even if they were not modified, just to reclaim memory: this will in turn

# force the clients to invalidate the cached values. Basically the table

# maximum size is a trade off between the memory you want to spend server

# side to track information about who cached what, and the ability of clients

# to retain cached objects in memory.

#

# If you set the value to 0, it means there are no limits, and Redis will

# retain as many keys as needed in the invalidation table.

# In the "stats" INFO section, you can find information about the number of

# keys in the invalidation table at every given moment.

#

# Note: when key tracking is used in broadcasting mode, no memory is used

# in the server side so this setting is useless.

#

# tracking-table-max-keys 1000000

################################## SECURITY ###################################

# Warning: since Redis is pretty fast, an outside user can try up to

# 1 million passwords per second against a modern box. This means that you

# should use very strong passwords, otherwise they will be very easy to break.

# Note that because the password is really a shared secret between the client

# and the server, and should not be memorized by any human, the password

# can be easily a long string from /dev/urandom or whatever, so by using a

# long and unguessable password no brute force attack will be possible.

# Redis ACL users are defined in the following format:

#

# user ... acl rules ...

#

# For example:

#

# user worker +@list +@connection ~jobs:* on >ffa9203c493aa99

#

# The special username "default" is used for new connections. If this user

# has the "nopass" rule, then new connections will be immediately authenticated

# as the "default" user without the need of any password provided via the

# AUTH command. Otherwise if the "default" user is not flagged with "nopass"

# the connections will start in not authenticated state, and will require

# AUTH (or the HELLO command AUTH option) in order to be authenticated and

# start to work.

#

# The ACL rules that describe what a user can do are the following:

#

# on Enable the user: it is possible to authenticate as this user.

# off Disable the user: it's no longer possible to authenticate

# with this user, however the already authenticated connections

# will still work.

# skip-sanitize-payload RESTORE dump-payload sanitization is skipped.

# sanitize-payload RESTORE dump-payload is sanitized (default).

# + Allow the execution of that command.

# May be used with `|` for allowing subcommands (e.g "+config|get")

# - Disallow the execution of that command.

# May be used with `|` for blocking subcommands (e.g "-config|set")

# +@ Allow the execution of all the commands in such category

# with valid categories are like @admin, @set, @sortedset, ...

# and so forth, see the full list in the server.c file where

# the Redis command table is described and defined.

# The special category @all means all the commands, but currently

# present in the server, and that will be loaded in the future

# via modules.

# +|first-arg Allow a specific first argument of an otherwise

# disabled command. It is only supported on commands with

# no sub-commands, and is not allowed as negative form

# like -SELECT|1, only additive starting with "+". This

# feature is deprecated and may be removed in the future.

# allcommands Alias for +@all. Note that it implies the ability to execute

# all the future commands loaded via the modules system.

# nocommands Alias for -@all.

# ~ Add a pattern of keys that can be mentioned as part of

# commands. For instance ~* allows all the keys. The pattern

# is a glob-style pattern like the one of KEYS.

# It is possible to specify multiple patterns.

# %R~ Add key read pattern that specifies which keys can be read

# from.

# %W~ Add key write pattern that specifies which keys can be

# written to.

# allkeys Alias for ~*

# resetkeys Flush the list of allowed keys patterns.

# & Add a glob-style pattern of Pub/Sub channels that can be

# accessed by the user. It is possible to specify multiple channel

# patterns.

# allchannels Alias for &*

# resetchannels Flush the list of allowed channel patterns.

# > Add this password to the list of valid password for the user.

# For example >mypass will add "mypass" to the list.

# This directive clears the "nopass" flag (see later).

# < Remove this password from the list of valid passwords.

# nopass All the set passwords of the user are removed, and the user

# is flagged as requiring no password: it means that every

# password will work against this user. If this directive is

# used for the default user, every new connection will be

# immediately authenticated with the default user without

# any explicit AUTH command required. Note that the "resetpass"

# directive will clear this condition.

# resetpass Flush the list of allowed passwords. Moreover removes the

# "nopass" status. After "resetpass" the user has no associated

# passwords and there is no way to authenticate without adding

# some password (or setting it as "nopass" later).

# reset Performs the following actions: resetpass, resetkeys, off,

# -@all. The user returns to the same state it has immediately

# after its creation.

# () Create a new selector with the options specified within the

# parentheses and attach it to the user. Each option should be

# space separated. The first character must be ( and the last

# character must be ).

# clearselectors Remove all of the currently attached selectors.

# Note this does not change the "root" user permissions,

# which are the permissions directly applied onto the

# user (outside the parentheses).

#

# ACL rules can be specified in any order: for instance you can start with

# passwords, then flags, or key patterns. However note that the additive

# and subtractive rules will CHANGE MEANING depending on the ordering.

# For instance see the following example:

#

# user alice on +@all -DEBUG ~* >somepassword

#

# This will allow "alice" to use all the commands with the exception of the

# DEBUG command, since +@all added all the commands to the set of the commands

# alice can use, and later DEBUG was removed. However if we invert the order

# of two ACL rules the result will be different:

#

# user alice on -DEBUG +@all ~* >somepassword

#

# Now DEBUG was removed when alice had yet no commands in the set of allowed

# commands, later all the commands are added, so the user will be able to

# execute everything.

#

# Basically ACL rules are processed left-to-right.

#

# The following is a list of command categories and their meanings:

# * keyspace - Writing or reading from keys, databases, or their metadata

# in a type agnostic way. Includes DEL, RESTORE, DUMP, RENAME, EXISTS, DBSIZE,

# KEYS, EXPIRE, TTL, FLUSHALL, etc. Commands that may modify the keyspace,

# key or metadata will also have `write` category. Commands that only read

# the keyspace, key or metadata will have the `read` category.

# * read - Reading from keys (values or metadata). Note that commands that don't

# interact with keys, will not have either `read` or `write`.

# * write - Writing to keys (values or metadata)

# * admin - Administrative commands. Normal applications will never need to use

# these. Includes REPLICAOF, CONFIG, DEBUG, SAVE, MONITOR, ACL, SHUTDOWN, etc.

# * dangerous - Potentially dangerous (each should be considered with care for

# various reasons). This includes FLUSHALL, MIGRATE, RESTORE, SORT, KEYS,

# CLIENT, DEBUG, INFO, CONFIG, SAVE, REPLICAOF, etc.

# * connection - Commands affecting the connection or other connections.

# This includes AUTH, SELECT, COMMAND, CLIENT, ECHO, PING, etc.

# * blocking - Potentially blocking the connection until released by another

# command.

# * fast - Fast O(1) commands. May loop on the number of arguments, but not the

# number of elements in the key.

# * slow - All commands that are not Fast.

# * pubsub - PUBLISH / SUBSCRIBE related

# * transaction - WATCH / MULTI / EXEC related commands.

# * scripting - Scripting related.

# * set - Data type: sets related.

# * sortedset - Data type: zsets related.

# * list - Data type: lists related.

# * hash - Data type: hashes related.

# * string - Data type: strings related.

# * bitmap - Data type: bitmaps related.

# * hyperloglog - Data type: hyperloglog related.

# * geo - Data type: geo related.

# * stream - Data type: streams related.

#

# For more information about ACL configuration please refer to

# the Redis web site at https://redis.io/topics/acl

# ACL LOG

#

# The ACL Log tracks failed commands and authentication events associated

# with ACLs. The ACL Log is useful to troubleshoot failed commands blocked

# by ACLs. The ACL Log is stored in memory. You can reclaim memory with

# ACL LOG RESET. Define the maximum entry length of the ACL Log below.

acllog-max-len 128

# Using an external ACL file

#

# Instead of configuring users here in this file, it is possible to use

# a stand-alone file just listing users. The two methods cannot be mixed:

# if you configure users here and at the same time you activate the external

# ACL file, the server will refuse to start.

#

# The format of the external ACL user file is exactly the same as the

# format that is used inside redis.conf to describe users.

#

# aclfile /etc/redis/users.acl

# IMPORTANT NOTE: starting with Redis 6 "requirepass" is just a compatibility

# layer on top of the new ACL system. The option effect will be just setting

# the password for the default user. Clients will still authenticate using

# AUTH as usually, or more explicitly with AUTH default

# if they follow the new protocol: both will work.

#

# The requirepass is not compatible with aclfile option and the ACL LOAD

# command, these will cause requirepass to be ignored.

#-------账号密码，默认没有设置---------------------

# requirepass foobared

# New users are initialized with restrictive permissions by default, via the

# equivalent of this ACL rule 'off resetkeys -@all'. Starting with Redis 6.2, it

# is possible to manage access to Pub/Sub channels with ACL rules as well. The

# default Pub/Sub channels permission if new users is controlled by the

# acl-pubsub-default configuration directive, which accepts one of these values:

#

# allchannels: grants access to all Pub/Sub channels

# resetchannels: revokes access to all Pub/Sub channels

#

# From Redis 7.0, acl-pubsub-default defaults to 'resetchannels' permission.

#

# acl-pubsub-default resetchannels

# Command renaming (DEPRECATED).

#

# ------------------------------------------------------------------------

# WARNING: avoid using this option if possible. Instead use ACLs to remove

# commands from the default user, and put them only in some admin user you

# create for administrative purposes.

# ------------------------------------------------------------------------

#

# 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 replicas may cause problems.

################################### CLIENTS ####################################

# 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'.

#

# IMPORTANT: When Redis Cluster is used, the max number of connections is also

# shared with the cluster bus: every node in the cluster will use two

# connections, one incoming and another outgoing. It is important to size the

# limit accordingly in case of very large clusters.

#-------------------设置最大连接数----------------------------------

# maxclients 10000

############################## MEMORY MANAGEMENT ################################

# Set a memory usage limit to the specified amount of bytes.

# When the memory limit is reached Redis will try to remove keys

# according to the eviction policy selected (see maxmemory-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 or LFU cache, or to

# set a hard memory limit for an instance (using the 'noeviction' policy).

#

# WARNING: If you have replicas attached to an instance with maxmemory on,

# the size of the output buffers needed to feed the replicas 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 replicas 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 replicas attached it is suggested that you set a lower

# limit for maxmemory so that there is some free RAM on the system for replica

# 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 one from the following behaviors:

#

# volatile-lru -> Evict using approximated LRU, only keys with an expire set.

# allkeys-lru -> Evict any key using approximated LRU.

# volatile-lfu -> Evict using approximated LFU, only keys with an expire set.

# allkeys-lfu -> Evict any key using approximated LFU.

# volatile-random -> Remove a random key having 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 evict anything, just return an error on write operations.

#

# LRU means Least Recently Used

# LFU means Least Frequently Used

#

# Both LRU, LFU and volatile-ttl are implemented using approximated

# randomized algorithms.

#

# Note: with any of the above policies, when there are no suitable keys for

# eviction, Redis will return an error on write operations that require

# more memory. These are usually commands that create new keys, add data or

# modify existing keys. A few examples are: SET, INCR, HSET, LPUSH, SUNIONSTORE,

# SORT (due to the STORE argument), and EXEC (if the transaction includes any

# command that requires memory).

#

# The default is:

#---------------redis清除key的策略，总共有前面的八种--------------------------------

# maxmemory-policy noeviction

# LRU, LFU and minimal TTL algorithms are not precise algorithms but approximated

# algorithms (in order to save memory), so you can tune it for speed or

# accuracy. By default Redis will check five keys and pick the one that was

# used least recently, you can change the sample size using the following

# configuration directive.

#

# The default of 5 produces good enough results. 10 Approximates very closely

# true LRU but costs more CPU. 3 is faster but not very accurate.

#

# maxmemory-samples 5

# Eviction processing is designed to function well with the default setting.

# If there is an unusually large amount of write traffic, this value may need to

# be increased. Decreasing this value may reduce latency at the risk of

# eviction processing effectiveness

# 0 = minimum latency, 10 = default, 100 = process without regard to latency

#

# maxmemory-eviction-tenacity 10

# Starting from Redis 5, by default a replica will ignore its maxmemory setting

# (unless it is promoted to master after a failover or manually). It means

# that the eviction of keys will be just handled by the master, sending the

# DEL commands to the replica as keys evict in the master side.

#

# This behavior ensures that masters and replicas stay consistent, and is usually

# what you want, however if your replica is writable, or you want the replica

# to have a different memory setting, and you are sure all the writes performed

# to the replica are idempotent, then you may change this default (but be sure

# to understand what you are doing).

#

# Note that since the replica by default does not evict, it may end using more

# memory than the one set via maxmemory (there are certain buffers that may

# be larger on the replica, or data structures may sometimes take more memory

# and so forth). So make sure you monitor your replicas and make sure they

# have enough memory to never hit a real out-of-memory condition before the

# master hits the configured maxmemory setting.

#

# replica-ignore-maxmemory yes

# Redis reclaims expired keys in two ways: upon access when those keys are

# found to be expired, and also in background, in what is called the

# "active expire key". The key space is slowly and interactively scanned

# looking for expired keys to reclaim, so that it is possible to free memory

# of keys that are expired and will never be accessed again in a short time.

#

# The default effort of the expire cycle will try to avoid having more than

# ten percent of expired keys still in memory, and will try to avoid consuming

# more than 25% of total memory and to add latency to the system. However

# it is possible to increase the expire "effort" that is normally set to

# "1", to a greater value, up to the value "10". At its maximum value the

# system will use more CPU, longer cycles (and technically may introduce

# more latency), and will tolerate less already expired keys still present

# in the system. It's a tradeoff between memory, CPU and latency.

#

# active-expire-effort 1

############################# LAZY FREEING ####################################

# Redis has two primitives to delete keys. One is called DEL and is a blocking

# deletion of the object. It means that the server stops processing new commands

# in order to reclaim all the memory associated with an object in a synchronous

# way. If the key deleted is associated with a small object, the time needed

# in order to execute the DEL command is very small and comparable to most other

# O(1) or O(log_N) commands in Redis. However if the key is associated with an

# aggregated value containing millions of elements, the server can block for

# a long time (even seconds) in order to complete the operation.

#

# For the above reasons Redis also offers non blocking deletion primitives

# such as UNLINK (non blocking DEL) and the ASYNC option of FLUSHALL and

# FLUSHDB commands, in order to reclaim memory in background. Those commands

# are executed in constant time. Another thread will incrementally free the

# object in the background as fast as possible.

#

# DEL, UNLINK and ASYNC option of FLUSHALL and FLUSHDB are user-controlled.

# It's up to the design of the application to understand when it is a good

# idea to use one or the other. However the Redis server sometimes has to

# delete keys or flush the whole database as a side effect of other operations.

# Specifically Redis deletes objects independently of a user call in the

# following scenarios:

#

# 1) On eviction, because of the maxmemory and maxmemory policy configurations,

# in order to make room for new data, without going over the specified

# memory limit.

# 2) Because of expire: when a key with an associated time to live (see the

# EXPIRE command) must be deleted from memory.

# 3) Because of a side effect of a command that stores data on a key that may

# already exist. For example the RENAME command may delete the old key

# content when it is replaced with another one. Similarly SUNIONSTORE

# or SORT with STORE option may delete existing keys. The SET command

# itself removes any old content of the specified key in order to replace

# it with the specified string.

# 4) During replication, when a replica performs a full resynchronization with

# its master, the content of the whole database is removed in order to

# load the RDB file just transferred.

#

# In all the above cases the default is to delete objects in a blocking way,

# like if DEL was called. However you can configure each case specifically

# in order to instead release memory in a non-blocking way like if UNLINK

# was called, using the following configuration directives.

lazyfree-lazy-eviction no

lazyfree-lazy-expire no

lazyfree-lazy-server-del no

replica-lazy-flush no

# It is also possible, for the case when to replace the user code DEL calls

# with UNLINK calls is not easy, to modify the default behavior of the DEL

# command to act exactly like UNLINK, using the following configuration

# directive:

lazyfree-lazy-user-del no

# FLUSHDB, FLUSHALL, SCRIPT FLUSH and FUNCTION FLUSH support both asynchronous and synchronous

# deletion, which can be controlled by passing the [SYNC|ASYNC] flags into the

# commands. When neither flag is passed, this directive will be used to determine

# if the data should be deleted asynchronously.

lazyfree-lazy-user-flush no

################################ THREADED I/O #################################

# Redis is mostly single threaded, however there are certain threaded

# operations such as UNLINK, slow I/O accesses and other things that are

# performed on side threads.

#

# Now it is also possible to handle Redis clients socket reads and writes

# in different I/O threads. Since especially writing is so slow, normally

# Redis users use pipelining in order to speed up the Redis performances per

# core, and spawn multiple instances in order to scale more. Using I/O

# threads it is possible to easily speedup two times Redis without resorting

# to pipelining nor sharding of the instance.

#

# By default threading is disabled, we suggest enabling it only in machines

# that have at least 4 or more cores, leaving at least one spare core.

# Using more than 8 threads is unlikely to help much. We also recommend using

# threaded I/O only if you actually have performance problems, with Redis

# instances being able to use a quite big percentage of CPU time, otherwise

# there is no point in using this feature.

#

# So for instance if you have a four cores boxes, try to use 2 or 3 I/O

# threads, if you have a 8 cores, try to use 6 threads. In order to

# enable I/O threads use the following configuration directive:

#

# io-threads 4

#

# Setting io-threads to 1 will just use the main thread as usual.

# When I/O threads are enabled, we only use threads for writes, that is

# to thread the write(2) syscall and transfer the client buffers to the

# socket. However it is also possible to enable threading of reads and

# protocol parsing using the following configuration directive, by setting

# it to yes:

#

# io-threads-do-reads no

#

# Usually threading reads doesn't help much.

#

# NOTE 1: This configuration directive cannot be changed at runtime via

# CONFIG SET. Also, this feature currently does not work when SSL is

# enabled.

#

# NOTE 2: If you want to test the Redis speedup using redis-benchmark, make

# sure you also run the benchmark itself in threaded mode, using the

# --threads option to match the number of Redis threads, otherwise you'll not

# be able to notice the improvements.

############################ KERNEL OOM CONTROL ##############################

# On Linux, it is possible to hint the kernel OOM killer on what processes

# should be killed first when out of memory.

#

# Enabling this feature makes Redis actively control the oom_score_adj value

# for all its processes, depending on their role. The default scores will

# attempt to have background child processes killed before all others, and

# replicas killed before masters.

#

# Redis supports these options:

#

# no: Don't make changes to oom-score-adj (default).

# yes: Alias to "relative" see below.

# absolute: Values in oom-score-adj-values are written as is to the kernel.

# relative: Values are used relative to the initial value of oom_score_adj when

# the server starts and are then clamped to a range of -1000 to 1000.

# Because typically the initial value is 0, they will often match the

# absolute values.

oom-score-adj no

# When oom-score-adj is used, this directive controls the specific values used

# for master, replica and background child processes. Values range -2000 to

# 2000 (higher means more likely to be killed).

#

# Unprivileged processes (not root, and without CAP_SYS_RESOURCE capabilities)

# can freely increase their value, but not decrease it below its initial

# settings. This means that setting oom-score-adj to "relative" and setting the

# oom-score-adj-values to positive values will always succeed.

oom-score-adj-values 0 200 800

#################### KERNEL transparent hugepage CONTROL ######################

# Usually the kernel Transparent Huge Pages control is set to "madvise" or

# or "never" by default (/sys/kernel/mm/transparent_hugepage/enabled), in which

# case this config has no effect. On systems in which it is set to "always",

# redis will attempt to disable it specifically for the redis process in order

# to avoid latency problems specifically with fork(2) and CoW.

# If for some reason you prefer to keep it enabled, you can set this config to

# "no" and the kernel global to "always".

disable-thp yes

############################## 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 https://redis.io/topics/persistence for more information.

appendonly no

# The base name of the append only file.

#

# Redis 7 and newer use a set of append-only files to persist the dataset

# and changes applied to it. There are two basic types of files in use:

#

# - Base files, which are a snapshot representing the complete state of the

# dataset at the time the file was created. Base files can be either in

# the form of RDB (binary serialized) or AOF (textual commands).

# - Incremental files, which contain additional commands that were applied

# to the dataset following the previous file.

#

# In addition, manifest files are used to track the files and the order in

# which they were created and should be applied.

#

# Append-only file names are created by Redis following a specific pattern.

# The file name's prefix is based on the 'appendfilename' configuration

# parameter, followed by additional information about the sequence and type.

#

# For example, if appendfilename is set to appendonly.aof, the following file

# names could be derived:

#

# - appendonly.aof.1.base.rdb as a base file.

# - appendonly.aof.1.incr.aof, appendonly.aof.2.incr.aof as incremental files.

# - appendonly.aof.manifest as a manifest file.

appendfilename "appendonly.aof"

# For convenience, Redis stores all persistent append-only files in a dedicated

# directory. The name of the directory is determined by the appenddirname

# configuration parameter.

appenddirname "appendonlydir"

# The fsync() call tells the Operating System to actually write data on disk

# instead of waiting 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 no". 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

# An AOF file may be found to be truncated at the end during the Redis

# startup process, when the AOF data gets loaded back into memory.

# This may happen when the system where Redis is running

# crashes, especially when an ext4 filesystem is mounted without the

# data=ordered option (however this can't happen when Redis itself

# crashes or aborts but the operating system still works correctly).

#

# Redis can either exit with an error when this happens, or load as much

# data as possible (the default now) and start if the AOF file is found

# to be truncated at the end. The following option controls this behavior.

#

# If aof-load-truncated is set to yes, a truncated AOF file is loaded and

# the Redis server starts emitting a log to inform the user of the event.

# Otherwise if the option is set to no, the server aborts with an error

# and refuses to start. When the option is set to no, the user requires

# to fix the AOF file using the "redis-check-aof" utility before to restart

# the server.

#

# Note that if the AOF file will be found to be corrupted in the middle

# the server will still exit with an error. This option only applies when

# Redis will try to read more data from the AOF file but not enough bytes

# will be found.

aof-load-truncated yes

# Redis can create append-only base files in either RDB or AOF formats. Using

# the RDB format is always faster and more efficient, and disabling it is only

# supported for backward compatibility purposes.

aof-use-rdb-preamble yes

# Redis supports recording timestamp annotations in the AOF to support restoring

# the data from a specific point-in-time. However, using this capability changes

# the AOF format in a way that may not be compatible with existing AOF parsers.

aof-timestamp-enabled no

################################ SHUTDOWN #####################################

# Maximum time to wait for replicas when shutting down, in seconds.

#

# During shut down, a grace period allows any lagging replicas to catch up with

# the latest replication offset before the master exists. This period can

# prevent data loss, especially for deployments without configured disk backups.

#

# The 'shutdown-timeout' value is the grace period's duration in seconds. It is

# only applicable when the instance has replicas. To disable the feature, set

# the value to 0.

#

# shutdown-timeout 10

# When Redis receives a SIGINT or SIGTERM, shutdown is initiated and by default

# an RDB snapshot is written to disk in a blocking operation if save points are configured.

# The options used on signaled shutdown can include the following values:

# default: Saves RDB snapshot only if save points are configured.

# Waits for lagging replicas to catch up.

# save: Forces a DB saving operation even if no save points are configured.

# nosave: Prevents DB saving operation even if one or more save points are configured.

# now: Skips waiting for lagging replicas.

# force: Ignores any errors that would normally prevent the server from exiting.

#

# Any combination of values is allowed as long as "save" and "nosave" are not set simultaneously.

# Example: "nosave force now"

#

# shutdown-on-sigint default

# shutdown-on-sigterm default

################ NON-DETERMINISTIC LONG BLOCKING COMMANDS #####################

# Maximum time in milliseconds for EVAL scripts, functions and in some cases

# modules' commands before Redis can start processing or rejecting other clients.

#

# If the maximum execution time is reached Redis will start to reply to most

# commands with a BUSY error.

#

# In this state Redis will only allow a handful of commands to be executed.

# For instance, SCRIPT KILL, FUNCTION KILL, SHUTDOWN NOSAVE and possibly some

# module specific 'allow-busy' commands.

#

# SCRIPT KILL and FUNCTION KILL will only be able to stop a script that did not

# yet call any write commands, so SHUTDOWN NOSAVE may be the only way to stop

# the server in the case a write command was already issued by the script when

# the user doesn't want to wait for the natural termination of the script.

#

# The default is 5 seconds. It is possible to set it to 0 or a negative value

# to disable this mechanism (uninterrupted execution). Note that in the past

# this config had a different name, which is now an alias, so both of these do

# the same:

# lua-time-limit 5000

# busy-reply-threshold 5000

################################ REDIS CLUSTER ###############################

# Normal Redis instances can't be part of a Redis Cluster; only nodes that are

# started as cluster nodes can. In order to start a Redis instance as a

# cluster node enable the cluster support uncommenting the following:

#

# cluster-enabled yes

# Every cluster node has a cluster configuration file. This file is not

# intended to be edited by hand. It is created and updated by Redis nodes.

# Every Redis Cluster node requires a different cluster configuration file.

# Make sure that instances running in the same system do not have

# overlapping cluster configuration file names.

#

# cluster-config-file nodes-6379.conf

# Cluster node timeout is the amount of milliseconds a node must be unreachable

# for it to be considered in failure state.

# Most other internal time limits are a multiple of the node timeout.

#

# cluster-node-timeout 15000

# The cluster port is the port that the cluster bus will listen for inbound connections on. When set

# to the default value, 0, it will be bound to the command port + 10000. Setting this value requires

# you to specify the cluster bus port when executing cluster meet.

# cluster-port 0

# A replica of a failing master will avoid to start a failover if its data

# looks too old.

#

# There is no simple way for a replica to actually have an exact measure of

# its "data age", so the following two checks are performed:

#

# 1) If there are multiple replicas able to failover, they exchange messages

# in order to try to give an advantage to the replica with the best

# replication offset (more data from the master processed).

# Replicas will try to get their rank by offset, and apply to the start

# of the failover a delay proportional to their rank.

#

# 2) Every single replica computes the time of the last interaction with

# its master. This can be the last ping or command received (if the master

# is still in the "connected" state), or the time that elapsed since the

# disconnection with the master (if the replication link is currently down).

# If the last interaction is too old, the replica will not try to failover

# at all.

#

# The point "2" can be tuned by user. Specifically a replica will not perform

# the failover if, since the last interaction with the master, the time

# elapsed is greater than:

#

# (node-timeout * cluster-replica-validity-factor) + repl-ping-replica-period

#

# So for example if node-timeout is 30 seconds, and the cluster-replica-validity-factor

# is 10, and assuming a default repl-ping-replica-period of 10 seconds, the

# replica will not try to failover if it was not able to talk with the master

# for longer than 310 seconds.

#

# A large cluster-replica-validity-factor may allow replicas with too old data to failover

# a master, while a too small value may prevent the cluster from being able to

# elect a replica at all.

#

# For maximum availability, it is possible to set the cluster-replica-validity-factor

# to a value of 0, which means, that replicas will always try to failover the

# master regardless of the last time they interacted with the master.

# (However they'll always try to apply a delay proportional to their

# offset rank).

#

# Zero is the only value able to guarantee that when all the partitions heal

# the cluster will always be able to continue.

#

# cluster-replica-validity-factor 10

# Cluster replicas are able to migrate to orphaned masters, that are masters

# that are left without working replicas. This improves the cluster ability

# to resist to failures as otherwise an orphaned master can't be failed over

# in case of failure if it has no working replicas.

#

# Replicas migrate to orphaned masters only if there are still at least a

# given number of other working replicas for their old master. This number

# is the "migration barrier". A migration barrier of 1 means that a replica

# will migrate only if there is at least 1 other working replica for its master

# and so forth. It usually reflects the number of replicas you want for every

# master in your cluster.

#

# Default is 1 (replicas migrate only if their masters remain with at least

# one replica). To disable migration just set it to a very large value or

# set cluster-allow-replica-migration to 'no'.

# A value of 0 can be set but is useful only for debugging and dangerous

# in production.

#

# cluster-migration-barrier 1

# Turning off this option allows to use less automatic cluster configuration.

# It both disables migration to orphaned masters and migration from masters

# that became empty.

#

# Default is 'yes' (allow automatic migrations).

#

# cluster-allow-replica-migration yes

# By default Redis Cluster nodes stop accepting queries if they detect there

# is at least a hash slot uncovered (no available node is serving it).

# This way if the cluster is partially down (for example a range of hash slots

# are no longer covered) all the cluster becomes, eventually, unavailable.

# It automatically returns available as soon as all the slots are covered again.

#

# However sometimes you want the subset of the cluster which is working,

# to continue to accept queries for the part of the key space that is still

# covered. In order to do so, just set the cluster-require-full-coverage

# option to no.

#

# cluster-require-full-coverage yes

# This option, when set to yes, prevents replicas from trying to failover its

# master during master failures. However the replica can still perform a

# manual failover, if forced to do so.

#

# This is useful in different scenarios, especially in the case of multiple

# data center operations, where we want one side to never be promoted if not

# in the case of a total DC failure.

#

# cluster-replica-no-failover no

# This option, when set to yes, allows nodes to serve read traffic while the

# cluster is in a down state, as long as it believes it owns the slots.

#

# This is useful for two cases. The first case is for when an application

# doesn't require consistency of data during node failures or network partitions.

# One example of this is a cache, where as long as the node has the data it

# should be able to serve it.

#

# The second use case is for configurations that don't meet the recommended

# three shards but want to enable cluster mode and scale later. A

# master outage in a 1 or 2 shard configuration causes a read/write outage to the

# entire cluster without this option set, with it set there is only a write outage.

# Without a quorum of masters, slot ownership will not change automatically.

#

# cluster-allow-reads-when-down no

# This option, when set to yes, allows nodes to serve pubsub shard traffic while

# the cluster is in a down state, as long as it believes it owns the slots.

#

# This is useful if the application would like to use the pubsub feature even when

# the cluster global stable state is not OK. If the application wants to make sure only

# one shard is serving a given channel, this feature should be kept as yes.

#

# cluster-allow-pubsubshard-when-down yes

# Cluster link send buffer limit is the limit on the memory usage of an individual

# cluster bus link's send buffer in bytes. Cluster links would be freed if they exceed

# this limit. This is to primarily prevent send buffers from growing unbounded on links

# toward slow peers (E.g. PubSub messages being piled up).

# This limit is disabled by default. Enable this limit when 'mem_cluster_links' INFO field

# and/or 'send-buffer-allocated' entries in the 'CLUSTER LINKS` command output continuously increase.

# Minimum limit of 1gb is recommended so that cluster link buffer can fit in at least a single

# PubSub message by default. (client-query-buffer-limit default value is 1gb)

#

# cluster-link-sendbuf-limit 0

# Clusters can configure their announced hostname using this config. This is a common use case for

# applications that need to use TLS Server Name Indication (SNI) or dealing with DNS based

# routing. By default this value is only shown as additional metadata in the CLUSTER SLOTS

# command, but can be changed using 'cluster-preferred-endpoint-type' config. This value is

# communicated along the clusterbus to all nodes, setting it to an empty string will remove

# the hostname and also propagate the removal.

#

# cluster-announce-hostname ""

# Clusters can advertise how clients should connect to them using either their IP address,

# a user defined hostname, or by declaring they have no endpoint. Which endpoint is

# shown as the preferred endpoint is set by using the cluster-preferred-endpoint-type

# config with values 'ip', 'hostname', or 'unknown-endpoint'. This value controls how

# the endpoint returned for MOVED/ASKING requests as well as the first field of CLUSTER SLOTS.

# If the preferred endpoint type is set to hostname, but no announced hostname is set, a '?'

# will be returned instead.

#

# When a cluster advertises itself as having an unknown endpoint, it's indicating that

# the server doesn't know how clients can reach the cluster. This can happen in certain

# networking situations where there are multiple possible routes to the node, and the

# server doesn't know which one the client took. In this case, the server is expecting

# the client to reach out on the same endpoint it used for making the last request, but use

# the port provided in the response.

#

# cluster-preferred-endpoint-type ip

# In order to setup your cluster make sure to read the documentation

# available at https://redis.io web site.

########################## CLUSTER DOCKER/NAT support ########################

# In certain deployments, Redis Cluster nodes address discovery fails, because

# addresses are NAT-ted or because ports are forwarded (the typical case is

# Docker and other containers).

#

# In order to make Redis Cluster working in such environments, a static

# configuration where each node knows its public address is needed. The

# following four options are used for this scope, and are:

#

# * cluster-announce-ip

# * cluster-announce-port

# * cluster-announce-tls-port

# * cluster-announce-bus-port

#

# Each instructs the node about its address, client ports (for connections

# without and with TLS) and cluster message bus port. The information is then

# published in the header of the bus packets so that other nodes will be able to

# correctly map the address of the node publishing the information.

#

# If cluster-tls is set to yes and cluster-announce-tls-port is omitted or set

# to zero, then cluster-announce-port refers to the TLS port. Note also that

# cluster-announce-tls-port has no effect if cluster-tls is set to no.

#

# If the above options are not used, the normal Redis Cluster auto-detection

# will be used instead.

#

# Note that when remapped, the bus port may not be at the fixed offset of

# clients port + 10000, so you can specify any port and bus-port depending

# on how they get remapped. If the bus-port is not set, a fixed offset of

# 10000 will be used as usual.

#

# Example:

#

# cluster-announce-ip 10.1.1.5

# cluster-announce-tls-port 6379

# cluster-announce-port 0

# cluster-announce-bus-port 6380

################################## 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

################################ LATENCY MONITOR ##############################

# The Redis latency monitoring subsystem samples different operations

# at runtime in order to collect data related to possible sources of

# latency of a Redis instance.

#

# Via the LATENCY command this information is available to the user that can

# print graphs and obtain reports.

#

# The system only logs operations that were performed in a time equal or

# greater than the amount of milliseconds specified via the

# latency-monitor-threshold configuration directive. When its value is set

# to zero, the latency monitor is turned off.

#

# By default latency monitoring is disabled since it is mostly not needed

# if you don't have latency issues, and collecting data has a performance

# impact, that while very small, can be measured under big load. Latency

# monitoring can easily be enabled at runtime using the command

# "CONFIG SET latency-monitor-threshold " if needed.

latency-monitor-threshold 0

################################ LATENCY TRACKING ##############################

# The Redis extended latency monitoring tracks the per command latencies and enables

# exporting the percentile distribution via the INFO latencystats command,

# and cumulative latency distributions (histograms) via the LATENCY command.

#

# By default, the extended latency monitoring is enabled since the overhead

# of keeping track of the command latency is very small.

# latency-tracking yes

# By default the exported latency percentiles via the INFO latencystats command

# are the p50, p99, and p999.

# latency-tracking-info-percentiles 50 99 99.9

############################# EVENT NOTIFICATION ##############################

# Redis can notify Pub/Sub clients about events happening in the key space.

# This feature is documented at https://redis.io/topics/notifications

#

# For instance if keyspace events notification is enabled, and a client

# performs a DEL operation on key "foo" stored in the Database 0, two

# messages will be published via Pub/Sub:

#

# PUBLISH __keyspace@0__:foo del

# PUBLISH __keyevent@0__:del foo

#

# It is possible to select the events that Redis will notify among a set

# of classes. Every class is identified by a single character:

#

# K Keyspace events, published with __keyspace@__ prefix.

# E Keyevent events, published with __keyevent@__ prefix.

# g Generic commands (non-type specific) like DEL, EXPIRE, RENAME, ...

# $ String commands

# l List commands

# s Set commands

# h Hash commands

# z Sorted set commands

# x Expired events (events generated every time a key expires)

# e Evicted events (events generated when a key is evicted for maxmemory)

# n New key events (Note: not included in the 'A' class)

# t Stream commands

# d Module key type events

# m Key-miss events (Note: It is not included in the 'A' class)

# A Alias for g$lshzxetd, so that the "AKE" string means all the events

# (Except key-miss events which are excluded from 'A' due to their

# unique nature).

#

# The "notify-keyspace-events" takes as argument a string that is composed

# of zero or multiple characters. The empty string means that notifications

# are disabled.

#

# Example: to enable list and generic events, from the point of view of the

# event name, use:

#

# notify-keyspace-events Elg

#

# Example 2: to get the stream of the expired keys subscribing to channel

# name __keyevent@0__:expired use:

#

# notify-keyspace-events Ex

#

# By default all notifications are disabled because most users don't need

# this feature and the feature has some overhead. Note that if you don't

# specify at least one of K or E, no events will be delivered.

notify-keyspace-events ""

############################### 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-listpack-entries 512

hash-max-listpack-value 64

# Lists are also encoded in a special way to save a lot of space.

# The number of entries allowed per internal list node can be specified

# as a fixed maximum size or a maximum number of elements.

# For a fixed maximum size, use -5 through -1, meaning:

# -5: max size: 64 Kb <-- not recommended for normal workloads

# -4: max size: 32 Kb <-- not recommended

# -3: max size: 16 Kb <-- probably not recommended

# -2: max size: 8 Kb <-- good

# -1: max size: 4 Kb <-- good

# Positive numbers mean store up to _exactly_ that number of elements

# per list node.

# The highest performing option is usually -2 (8 Kb size) or -1 (4 Kb size),

# but if your use case is unique, adjust the settings as necessary.

list-max-listpack-size -2

# Lists may also be compressed.

# Compress depth is the number of quicklist ziplist nodes from *each* side of

# the list to *exclude* from compression. The head and tail of the list

# are always uncompressed for fast push/pop operations. Settings are:

# 0: disable all list compression

# 1: depth 1 means "don't start compressing until after 1 node into the list,

# going from either the head or tail"

# So: [head]->node->node->...->node->[tail]

# [head], [tail] will always be uncompressed; inner nodes will compress.

# 2: [head]->[next]->node->node->...->node->[prev]->[tail]

# 2 here means: don't compress head or head->next or tail->prev or tail,

# but compress all nodes between them.

# 3: [head]->[next]->[next]->node->node->...->node->[prev]->[prev]->[tail]

# etc.

list-compress-depth 0

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

# of just strings that happen 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-listpack-entries 128

zset-max-listpack-value 64

# HyperLogLog sparse representation bytes limit. The limit includes the

# 16 bytes header. When an HyperLogLog using the sparse representation crosses

# this limit, it is converted into the dense representation.

#

# A value greater than 16000 is totally useless, since at that point the

# dense representation is more memory efficient.

#

# The suggested value is ~ 3000 in order to have the benefits of

# the space efficient encoding without slowing down too much PFADD,

# which is O(N) with the sparse encoding. The value can be raised to

# ~ 10000 when CPU is not a concern, but space is, and the data set is

# composed of many HyperLogLogs with cardinality in the 0 - 15000 range.

hll-sparse-max-bytes 3000

# Streams macro node max size / items. The stream data structure is a radix

# tree of big nodes that encode multiple items inside. Using this configuration

# it is possible to configure how big a single node can be in bytes, and the

# maximum number of items it may contain before switching to a new node when

# appending new stream entries. If any of the following settings are set to

# zero, the limit is ignored, so for instance it is possible to set just a

# max entries limit by setting max-bytes to 0 and max-entries to the desired

# value.

stream-node-max-bytes 4096

stream-node-max-entries 100

# 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 a 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

# actively rehash 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 from 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 including MONITOR clients

# replica -> replica clients

# pubsub -> clients subscribed 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 replica clients, since

# subscribers and replicas receive data in a push fashion.

#

# Note that it doesn't make sense to set the replica clients output buffer

# limit lower than the repl-backlog-size config (partial sync will succeed

# and then replica will get disconnected).

# Such a configuration is ignored (the size of repl-backlog-size will be used).

# This doesn't have memory consumption implications since the replica client

# will share the backlog buffers memory.

#

# 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 replica 256mb 64mb 60

client-output-buffer-limit pubsub 32mb 8mb 60

# Client query buffers accumulate new commands. They are limited to a fixed

# amount by default in order to avoid that a protocol desynchronization (for

# instance due to a bug in the client) will lead to unbound memory usage in

# the query buffer. However you can configure it here if you have very special

# needs, such us huge multi/exec requests or alike.

#

# client-query-buffer-limit 1gb

# In some scenarios client connections can hog up memory leading to OOM

# errors or data eviction. To avoid this we can cap the accumulated memory

# used by all client connections (all pubsub and normal clients). Once we

# reach that limit connections will be dropped by the server freeing up

# memory. The server will attempt to drop the connections using the most

# memory first. We call this mechanism "client eviction".

#

# Client eviction is configured using the maxmemory-clients setting as follows:

# 0 - client eviction is disabled (default)

#

# A memory value can be used for the client eviction threshold,

# for example:

# maxmemory-clients 1g

#

# A percentage value (between 1% and 100%) means the client eviction threshold

# is based on a percentage of the maxmemory setting. For example to set client

# eviction at 5% of maxmemory:

# maxmemory-clients 5%

# In the Redis protocol, bulk requests, that are, elements representing single

# strings, are normally limited to 512 mb. However you can change this limit

# here, but must be 1mb or greater

#

# proto-max-bulk-len 512mb

# Redis calls an internal function to perform many background tasks, like

# closing connections of clients in timeout, purging expired keys that are

# never requested, and so forth.

#

# Not all tasks are performed with the same frequency, but Redis checks for

# tasks to perform according 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

# Normally it is useful to have an HZ value which is proportional to the

# number of clients connected. This is useful in order, for instance, to

# avoid too many clients are processed for each background task invocation

# in order to avoid latency spikes.

#

# Since the default HZ value by default is conservatively set to 10, Redis

# offers, and enables by default, the ability to use an adaptive HZ value

# which will temporarily raise when there are many connected clients.

#

# When dynamic HZ is enabled, the actual configured HZ will be used

# as a baseline, but multiples of the configured HZ value will be actually

# used as needed once more clients are connected. In this way an idle

# instance will use very little CPU time while a busy instance will be

# more responsive.

dynamic-hz yes

# When a child rewrites the AOF file, if the following option is enabled

# the file will be fsync-ed every 4 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

# When redis saves RDB file, if the following option is enabled

# the file will be fsync-ed every 4 MB of data generated. This is useful

# in order to commit the file to the disk more incrementally and avoid

# big latency spikes.

rdb-save-incremental-fsync yes

# Redis LFU eviction (see maxmemory setting) can be tuned. However it is a good

# idea to start with the default settings and only change them after investigating

# how to improve the performances and how the keys LFU change over time, which

# is possible to inspect via the OBJECT FREQ command.

#

# There are two tunable parameters in the Redis LFU implementation: the

# counter logarithm factor and the counter decay time. It is important to

# understand what the two parameters mean before changing them.

#

# The LFU counter is just 8 bits per key, it's maximum value is 255, so Redis

# uses a probabilistic increment with logarithmic behavior. Given the value

# of the old counter, when a key is accessed, the counter is incremented in

# this way:

#

# 1. A random number R between 0 and 1 is extracted.

# 2. A probability P is calculated as 1/(old_value*lfu_log_factor+1).

# 3. The counter is incremented only if R < P.

#

# The default lfu-log-factor is 10. This is a table of how the frequency

# counter changes with a different number of accesses with different

# logarithmic factors:

#

# +--------+------------+------------+------------+------------+------------+

# | factor | 100 hits | 1000 hits | 100K hits | 1M hits | 10M hits |

# +--------+------------+------------+------------+------------+------------+

# | 0 | 104 | 255 | 255 | 255 | 255 |

# +--------+------------+------------+------------+------------+------------+

# | 1 | 18 | 49 | 255 | 255 | 255 |

# +--------+------------+------------+------------+------------+------------+

# | 10 | 10 | 18 | 142 | 255 | 255 |

# +--------+------------+------------+------------+------------+------------+

# | 100 | 8 | 11 | 49 | 143 | 255 |

# +--------+------------+------------+------------+------------+------------+

#

# NOTE: The above table was obtained by running the following commands:

#

# redis-benchmark -n 1000000 incr foo

# redis-cli object freq foo

#

# NOTE 2: The counter initial value is 5 in order to give new objects a chance

# to accumulate hits.

#

# The counter decay time is the time, in minutes, that must elapse in order

# for the key counter to be divided by two (or decremented if it has a value

# less <= 10).

#

# The default value for the lfu-decay-time is 1. A special value of 0 means to

# decay the counter every time it happens to be scanned.

#

# lfu-log-factor 10

# lfu-decay-time 1

########################### ACTIVE DEFRAGMENTATION #######################

#

# What is active defragmentation?

# -------------------------------

#

# Active (online) defragmentation allows a Redis server to compact the

# spaces left between small allocations and deallocations of data in memory,

# thus allowing to reclaim back memory.

#

# Fragmentation is a natural process that happens with every allocator (but

# less so with Jemalloc, fortunately) and certain workloads. Normally a server

# restart is needed in order to lower the fragmentation, or at least to flush

# away all the data and create it again. However thanks to this feature

# implemented by Oran Agra for Redis 4.0 this process can happen at runtime

# in a "hot" way, while the server is running.

#

# Basically when the fragmentation is over a certain level (see the

# configuration options below) Redis will start to create new copies of the

# values in contiguous memory regions by exploiting certain specific Jemalloc

# features (in order to understand if an allocation is causing fragmentation

# and to allocate it in a better place), and at the same time, will release the

# old copies of the data. This process, repeated incrementally for all the keys

# will cause the fragmentation to drop back to normal values.

#

# Important things to understand:

#

# 1. This feature is disabled by default, and only works if you compiled Redis

# to use the copy of Jemalloc we ship with the source code of Redis.

# This is the default with Linux builds.

#

# 2. You never need to enable this feature if you don't have fragmentation

# issues.

#

# 3. Once you experience fragmentation, you can enable this feature when

# needed with the command "CONFIG SET activedefrag yes".

#

# The configuration parameters are able to fine tune the behavior of the

# defragmentation process. If you are not sure about what they mean it is

# a good idea to leave the defaults untouched.

# Active defragmentation is disabled by default

# activedefrag no

# Minimum amount of fragmentation waste to start active defrag

# active-defrag-ignore-bytes 100mb

# Minimum percentage of fragmentation to start active defrag

# active-defrag-threshold-lower 10

# Maximum percentage of fragmentation at which we use maximum effort

# active-defrag-threshold-upper 100

# Minimal effort for defrag in CPU percentage, to be used when the lower

# threshold is reached

# active-defrag-cycle-min 1

# Maximal effort for defrag in CPU percentage, to be used when the upper

# threshold is reached

# active-defrag-cycle-max 25

# Maximum number of set/hash/zset/list fields that will be processed from

# the main dictionary scan

# active-defrag-max-scan-fields 1000

# Jemalloc background thread for purging will be enabled by default

jemalloc-bg-thread yes

# It is possible to pin different threads and processes of Redis to specific

# CPUs in your system, in order to maximize the performances of the server.

# This is useful both in order to pin different Redis threads in different

# CPUs, but also in order to make sure that multiple Redis instances running

# in the same host will be pinned to different CPUs.

#

# Normally you can do this using the "taskset" command, however it is also

# possible to this via Redis configuration directly, both in Linux and FreeBSD.

#

# You can pin the server/IO threads, bio threads, aof rewrite child process, and

# the bgsave child process. The syntax to specify the cpu list is the same as

# the taskset command:

#

# Set redis server/io threads to cpu affinity 0,2,4,6:

# server_cpulist 0-7:2

#

# Set bio threads to cpu affinity 1,3:

# bio_cpulist 1,3

#

# Set aof rewrite child process to cpu affinity 8,9,10,11:

# aof_rewrite_cpulist 8-11

#

# Set bgsave child process to cpu affinity 1,10,11

# bgsave_cpulist 1,10-11

# In some cases redis will emit warnings and even refuse to start if it detects

# that the system is in bad state, it is possible to suppress these warnings

# by setting the following config which takes a space delimited list of warnings

# to suppress

#

# ignore-warnings ARM64-COW-BUG