TODO updated

[redis.git] / redis.conf

diff --git a/redis.conf b/redis.conf
index 4c9377161bfdc7d87b0ec2240460e65d3342dc00..b087417a8ca81fc16714bba1cf0e7f4e0fdb372e 100644 (file)
--- a/redis.conf
+++ b/redis.conf
@@ -1,18 +1,30 @@
 # Redis configuration file example
 
 # Redis configuration file example
 

+# Note on units: when memory size is needed, it is possible to specifiy
+# it in the usual form of 1k 5GB 4M and so forth:
+#
+# 1k => 1000 bytes
+# 1kb => 1024 bytes
+# 1m => 1000000 bytes
+# 1mb => 1024*1024 bytes
+# 1g => 1000000000 bytes
+# 1gb => 1024*1024*1024 bytes
+#
+# units are case insensitive so 1GB 1Gb 1gB are all the same.
+

 # By default Redis does not run as a daemon. Use 'yes' if you need it.
 # Note that Redis will write a pid file in /var/run/redis.pid when daemonized.
 daemonize no
 
 # By default Redis does not run as a daemon. Use 'yes' if you need it.
 # Note that Redis will write a pid file in /var/run/redis.pid when daemonized.
 daemonize no
 

-# When run as a daemon, Redis write a pid file in /var/run/redis.pid by default.
-# You can specify a custom pid file location here.
+# When running daemonized, Redis writes a pid file in /var/run/redis.pid by
+# default. You can specify a custom pid file location here.

 pidfile /var/run/redis.pid
 
 # Accept connections on the specified port, default is 6379
 port 6379
 
 # If you want you can bind a single interface, if the bind option is not
 pidfile /var/run/redis.pid
 
 # Accept connections on the specified port, default is 6379
 port 6379
 
 # If you want you can bind a single interface, if the bind option is not

-# specified all the interfaces will listen for connections.
+# specified all the interfaces will listen for incoming connections.

 #
 # bind 127.0.0.1
 
 #
 # bind 127.0.0.1
 


@@ -22,12 +34,13 @@ timeout 300
 # Set server verbosity to 'debug'
 # it can be one of:
 # debug (a lot of information, useful for development/testing)
 # Set server verbosity to 'debug'
 # it can be one of:
 # debug (a lot of information, useful for development/testing)

+# verbose (many rarely useful info, but not a mess like the debug level)

 # notice (moderately verbose, what you want in production probably)
 # warning (only very important / critical messages are logged)
 loglevel verbose
 
 # Specify the log file name. Also 'stdout' can be used to force
 # notice (moderately verbose, what you want in production probably)
 # warning (only very important / critical messages are logged)
 loglevel verbose
 
 # Specify the log file name. Also 'stdout' can be used to force

-# the demon to log on the standard output. Note that if you use standard
+# Redis to log on the standard output. Note that if you use standard

 # output for logging but daemonize, logs will be sent to /dev/null
 logfile stdout
 
 # output for logging but daemonize, logs will be sent to /dev/null
 logfile stdout
 


@@ -52,9 +65,9 @@ databases 16
 #
 #   Note: you can disable saving at all commenting all the "save" lines.
 
 #
 #   Note: you can disable saving at all commenting all the "save" lines.
 

-#save 900 1
-#save 300 10
-#save 60 10000
+save 900 1
+save 300 10
+save 60 10000

 
 # Compress string objects using LZF when dump .rdb databases?
 # For default that's set to 'yes' as it's almost always a win.
 
 # Compress string objects using LZF when dump .rdb databases?
 # For default that's set to 'yes' as it's almost always a win.


@@ -65,8 +78,14 @@ rdbcompression yes
 # The filename where to dump the DB
 dbfilename dump.rdb
 
 # The filename where to dump the DB
 dbfilename dump.rdb
 

-# For default save/load DB in/from the working directory
-# Note that you must specify a directory not a file name.
+# The working directory.
+#
+# The DB will be written inside this directory, with the filename specified
+# above using the 'dbfilename' configuration directive.
+# 
+# Also the Append Only File will be created inside this directory.
+# 
+# Note that you must specify a directory here, not a file name.

 dir ./
 
 ################################# REPLICATION #################################
 dir ./
 
 ################################# REPLICATION #################################


@@ -93,6 +112,10 @@ dir ./
 #
 # This should stay commented out for backward compatibility and because most
 # people do not need auth (e.g. they run their own servers).
 #
 # This should stay commented out for backward compatibility and because most
 # people do not need auth (e.g. they run their own servers).

+# 
+# Warning: since Redis is pretty fast an outside user can try up to
+# 150k passwords per second against a good box. This means that you should
+# use a very strong password otherwise it will be very easy to break.

 #
 # requirepass foobared
 
 #
 # requirepass foobared
 


@@ -100,7 +123,7 @@ dir ./
 
 # Set the max number of connected clients at the same time. By default there
 # is no limit, and it's up to the number of file descriptors the Redis process
 
 # Set the max number of connected clients at the same time. By default there
 # is no limit, and it's up to the number of file descriptors the Redis process

-# is able to open. The special value '0' means no limts.
+# is able to open. The special value '0' means no limits.

 # Once the limit is reached Redis will close all the new connections sending
 # an error 'max number of clients reached'.
 #
 # Once the limit is reached Redis will close all the new connections sending
 # an error 'max number of clients reached'.
 #


@@ -132,7 +155,7 @@ dir ./
 # happens this is the preferred way to run Redis. If instead you care a lot
 # about your data and don't want to that a single record can get lost you should
 # enable the append only mode: when this mode is enabled Redis will append
 # happens this is the preferred way to run Redis. If instead you care a lot
 # about your data and don't want to that a single record can get lost you should
 # enable the append only mode: when this mode is enabled Redis will append

-# every write operation received in the file appendonly.log. This file will
+# every write operation received in the file appendonly.aof. This file will

 # be read on startup in order to rebuild the full dataset in memory.
 #
 # Note that you can have both the async dumps and the append only file if you
 # be read on startup in order to rebuild the full dataset in memory.
 #
 # Note that you can have both the async dumps and the append only file if you


@@ -140,13 +163,14 @@ dir ./
 # Still if append only mode is enabled Redis will load the data from the
 # log file at startup ignoring the dump.rdb file.
 #
 # Still if append only mode is enabled Redis will load the data from the
 # log file at startup ignoring the dump.rdb file.
 #

-# The name of the append only file is "appendonly.log"
-#

 # IMPORTANT: Check the BGREWRITEAOF to check how to rewrite the append
 # log file in background when it gets too big.
 
 appendonly no
 
 # IMPORTANT: Check the BGREWRITEAOF to check how to rewrite the append
 # log file in background when it gets too big.
 
 appendonly no
 

+# The name of the append only file (default: "appendonly.aof")
+# appendfilename appendonly.aof
+

 # The fsync() call tells the Operating System to actually write data on disk
 # instead to wait for more data in the output buffer. Some OS will really flush 
 # data on disk, some other OS will just try to do it ASAP.
 # The fsync() call tells the Operating System to actually write data on disk
 # instead to wait for more data in the output buffer. Some OS will really flush 
 # data on disk, some other OS will just try to do it ASAP.


@@ -157,16 +181,40 @@ appendonly no
 # always: fsync after every write to the append only log . Slow, Safest.
 # everysec: fsync only if one second passed since the last fsync. Compromise.
 #
 # always: fsync after every write to the append only log . Slow, Safest.
 # everysec: fsync only if one second passed since the last fsync. Compromise.
 #

-# The default is "always" that's the safer of the options. It's up to you to
-# understand if you can relax this to "everysec" that will fsync every second
-# or to "no" that will let the operating system flush the output buffer when
-# it want, for better performances (but if you can live with the idea of
-# some data loss consider the default persistence mode that's snapshotting).
+# The default is "everysec" 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 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.
+#
+# If unsure, use "everysec".

 
 

-appendfsync always
-# appendfsync everysec
+# appendfsync always
+appendfsync everysec

 # appendfsync no
 
 # appendfsync no
 

+# When the AOF fsync policy is set to always or everysec, and a background
+# saving process (a background save or AOF log background rewriting) is
+# performing a lot of I/O against the disk, in some Linux configurations
+# Redis may block too long on the fsync() call. Note that there is no fix for
+# this currently, as even performing fsync in a different thread will block
+# our synchronous write(2) call.
+#
+# In order to mitigate this problem it's possible to use the following option
+# that will prevent fsync() from being called in the main process while a
+# BGSAVE or BGREWRITEAOF is in progress.
+#
+# This means that while another child is saving the durability of Redis is
+# the same as "appendfsync none", that in pratical terms means that it is
+# possible to lost 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
+

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


@@ -178,13 +226,31 @@ appendfsync always
 # To enable VM just set 'vm-enabled' to yes, and set the following three
 # VM parameters accordingly to your needs.
 
 # To enable VM just set 'vm-enabled' to yes, and set the following three
 # VM parameters accordingly to your needs.
 

-vm-enabled yes
-# vm-enabled no
+vm-enabled no
+# vm-enabled yes
+
+# This is the path of the Redis swap file. As you can guess, swap files
+# can't be shared by different Redis instances, so make sure to use a swap
+# file for every redis process you are running. Redis will complain if the
+# swap file is already in use.
+#
+# The best kind of storage for the Redis swap file (that's accessed at random) 
+# is a Solid State Disk (SSD).
+#
+# *** WARNING *** if you are using a shared hosting the default of putting
+# the swap file under /tmp is not secure. Create a dir with access granted
+# only to Redis user and configure Redis to create the swap file there.
+vm-swap-file /tmp/redis.swap

 
 # vm-max-memory configures the VM to use at max the specified amount of
 # RAM. Everything that deos not fit will be swapped on disk *if* possible, that
 # is, if there is still enough contiguous space in the swap file.
 
 # vm-max-memory configures the VM to use at max the specified amount of
 # RAM. Everything that deos not fit will be swapped on disk *if* possible, that
 # is, if there is still enough contiguous space in the swap file.

-vm-max-memory 10000000
+#
+# With vm-max-memory 0 the system will swap everything it can. Not a good
+# default, just specify the max amount of RAM you can in bytes, but it's
+# better to leave some margin. For instance specify an amount of RAM
+# that's more or less between 60 and 80% of your free RAM.
+vm-max-memory 0

 
 # Redis swap files is split into pages. An object can be saved using multiple
 # contiguous pages, but pages can't be shared between different objects.
 
 # Redis swap files is split into pages. An object can be saved using multiple
 # contiguous pages, but pages can't be shared between different objects.


@@ -194,8 +260,8 @@ vm-max-memory 10000000
 #
 # If you use a lot of small objects, use a page size of 64 or 32 bytes.
 # If you use a lot of big objects, use a bigger page size.
 #
 # If you use a lot of small objects, use a page size of 64 or 32 bytes.
 # If you use a lot of big objects, use a bigger page size.

-# If unsure, use the defualt :)
-vm-page-size 256
+# If unsure, use the default :)
+vm-page-size 32

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


@@ -203,9 +269,23 @@ vm-page-size 256
 #
 # The total swap size is vm-page-size * vm-pages
 #
 #
 # The total swap size is vm-page-size * vm-pages
 #

-# With the default of 256-bytes memory pages and 104857600 pages Redis will
-# use a 25 GB swap file, that will use rougly 13 MB of RAM for the page table.
-vm-pages 104857600
+# With the default of 32-bytes memory pages and 134217728 pages Redis will
+# use a 4 GB swap file, that will use 16 MB of RAM for the page table.
+#
+# It's better to use the smallest acceptable value for your application,
+# but the default is large in order to work in most conditions.
+vm-pages 134217728
+
+# Max number of VM I/O threads running at the same time.
+# This threads are used to read/write data from/to swap file, since they
+# also encode and decode objects from disk to memory or the reverse, a bigger
+# number of threads can help with big objects even if they can't help with
+# I/O itself as the physical device may not be able to couple with many
+# reads/writes operations at the same time.
+#
+# The special value of 0 turn off threaded I/O and enables the blocking
+# Virtual Memory implementation.
+vm-max-threads 4

 
 ############################### ADVANCED CONFIG ###############################
 
 
 ############################### ADVANCED CONFIG ###############################
 


@@ -214,19 +294,39 @@ vm-pages 104857600
 # in terms of number of queries per second. Use 'yes' if unsure.
 glueoutputbuf yes
 
 # in terms of number of queries per second. Use 'yes' if unsure.
 glueoutputbuf yes
 

-# Use object sharing. Can save a lot of memory if you have many common
-# string in your dataset, but performs lookups against the shared objects
-# pool so it uses more CPU and can be a bit slower. Usually it's a good
-# idea.
-#
-# When object sharing is enabled (shareobjects yes) you can use
-# shareobjectspoolsize to control the size of the pool used in order to try
-# object sharing. A bigger pool size will lead to better sharing capabilities.
-# In general you want this value to be at least the double of the number of
-# very common strings you have in your dataset.
-#
-# WARNING: object sharing is experimental, don't enable this feature
-# in production before of Redis 1.0-stable. Still please try this feature in
-# your development environment so that we can test it better.
-shareobjects no
-shareobjectspoolsize 1024
+# Hashes are encoded in a special way (much more memory efficient) when they
+# have at max a given numer of elements, and the biggest element does not
+# exceed a given threshold. You can configure this limits with the following
+# configuration directives.
+hash-max-zipmap-entries 64
+hash-max-zipmap-value 512
+
+# Active rehashing uses 1 millisecond every 100 milliseconds of CPU time in
+# order to help rehashing the main Redis hash table (the one mapping top-level
+# keys to values). The hash table implementation redis uses (see dict.c)
+# performs a lazy rehashing: the more operation you run into an hash table
+# that is rhashing, the more rehashing "steps" are performed, so if the
+# server is idle the rehashing is never complete and some more memory is used
+# by the hash table.
+# 
+# The default is to use this millisecond 10 times every second in order to
+# active rehashing the main dictionaries, freeing memory when possible.
+#
+# If unsure:
+# use "activerehashing no" if you have hard latency requirements and it is
+# not a good thing in your environment that Redis can reply form time to time
+# to queries with 2 milliseconds delay.
+#
+# use "activerehashing yes" if you don't have such hard requirements but
+# want to free memory asap when possible.
+activerehashing yes
+
+################################## INCLUDES ###################################
+
+# Include one or more other config files here.  This is useful if you
+# have a standard template that goes to all redis server but also need
+# to customize a few per-server settings.  Include files can include
+# other files, so use this wisely.
+#
+# include /path/to/local.conf
+# include /path/to/other.conf