# Redis configuration file example
-# Note on units: when memory size is needed, it is possible to specifiy
+# 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:
#
# 1k => 1000 bytes
# after 60 sec if at least 10000 keys changed
#
# Note: you can disable saving at all commenting all the "save" lines.
+#
+# It is also possible to remove all the previously configured save
+# points by adding a save directive with a single empty string argument
+# like in the following example:
+#
+# save ""
save 900 1
save 300 10
# Command renaming.
#
-# It is possilbe to change the name of dangerous commands in a shared
+# It is possible to change the name of dangerous commands in a shared
# environment. For instance the CONFIG command may be renamed into something
# of hard to guess so that it will be still available for internal-use
# tools but not available for general clients.
#
# rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52
#
-# It is also possilbe to completely kill a command renaming it into
+# It is also possible to completely kill a command renaming it into
# an empty string:
#
# rename-command CONFIG ""
# maxclients 10000
# Don't use more memory than the specified amount of bytes.
-# When the memory limit is reached Redis will try to remove keys with an
-# EXPIRE set. It will try to start freeing keys that are going to expire
-# in little time and preserve keys with a longer time to live.
-# Redis will also try to remove objects from free lists if possible.
-#
-# If all this fails, Redis will start to reply with errors to commands
-# that will use more memory, like SET, LPUSH, and so on, and will continue
-# to reply to most read-only commands like GET.
-#
-# WARNING: maxmemory can be a good idea mainly if you want to use Redis as a
-# 'state' server or cache, not as a real DB. When Redis is used as a real
-# database the memory usage will grow over the weeks, it will be obvious if
-# it is going to use too much memory in the long run, and you'll have the time
-# to upgrade. With maxmemory after the limit is reached you'll start to get
-# errors for write operations, and this may even lead to DB inconsistency.
+# When the memory limit is reached Redis will try to remove keys
+# accordingly to the eviction policy selected (see maxmemmory-policy).
+#
+# If Redis can't remove keys according to the policy, or if the policy is
+# set to 'noeviction', Redis will start to reply with errors to commands
+# that would use more memory, like SET, LPUSH, and so on, and will continue
+# to reply to read-only commands like GET.
+#
+# This option is usually useful when using Redis as an LRU cache, or to set
+# an hard memory limit for an instance (using the 'noeviction' policy).
+#
+# WARNING: If you have slaves attached to an instance with maxmemory on,
+# the size of the output buffers needed to feed the slaves are subtracted
+# from the used memory count, so that network problems / resyncs will
+# not trigger a loop where keys are evicted, and in turn the output
+# buffer of slaves is full with DELs of keys evicted triggering the deletion
+# of more keys, and so forth until the database is completely emptied.
+#
+# In short... if you have slaves attached it is suggested that you set a lower
+# limit for maxmemory so that there is some free RAM on the system for slave
+# output buffers (but this is not needed if the policy is 'noeviction').
#
# maxmemory <bytes>
# 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
+# the same as "appendfsync none", that in practical terms means that it is
# possible to lost up to 30 seconds of log in the worst scenario (with the
# default Linux settings).
#
# is useful to avoid rewriting the AOF file even if the percentage increase
# is reached but it is still pretty small.
#
-# Specify a precentage of zero in order to disable the automatic AOF
+# Specify a percentage of zero in order to disable the automatic AOF
# rewrite feature.
auto-aof-rewrite-percentage 100
# Max execution time of a Lua script in milliseconds.
#
# If the maximum execution time is reached Redis will log that a script is
-# still in execution after the maxium allowed time and will start to
+# still in execution after the maximum allowed time and will start to
# reply to queries with an error.
#
-# When a long running script exceed the maxium execution time only the
+# When a long running script exceed the maximum execution time only the
# SCRIPT KILL and SHUTDOWN NOSAVE commands are available. The first can be
# used to stop a script that did not yet called write commands. The second
# is the only way to shut down the server in the case a write commands was
############################### ADVANCED CONFIG ###############################
# 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
+# have at max a given number of elements, and the biggest element does not
# exceed a given threshold. You can configure this limits with the following
# configuration directives.
hash-max-zipmap-entries 512
# 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)
+# 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
+# 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.
#
# want to free memory asap when possible.
activerehashing yes
+# The client output buffer limits can be used to force disconnection of clients
+# that are not reading data from the server fast enough for some reason (a
+# common reason is that a Pub/Sub client can't consume messages as fast as the
+# publisher can produce them).
+#
+# The limit can be set differently for the three different classes of clients:
+#
+# normal -> normal clients
+# slave -> slave clients and MONITOR clients
+# pubsub -> clients subcribed to at least one pubsub channel or pattern
+#
+# The syntax of every client-output-buffer-limit directive is the following:
+#
+# client-output-buffer-limit <class> <hard limit> <soft limit> <soft seconds>
+#
+# A client is immediately disconnected once the hard limit is reached, or if
+# the soft limit is reached and remains reached for the specified number of
+# seconds (continuously).
+# So for instance if the hard limit is 32 megabytes and the soft limit is
+# 16 megabytes / 10 seconds, the client will get disconnected immediately
+# if the size of the output buffers reach 32 megabytes, but will also get
+# disconnected if the client reaches 16 megabytes and continuously overcomes
+# the limit for 10 seconds.
+#
+# By default normal clients are not limited because they don't receive data
+# without asking (in a push way), but just after a request, so only
+# asynchronous clients may create a scenario where data is requested faster
+# than it can read.
+#
+# Instead there is a default limit for pubsub and slave clients, since
+# subscribers and slaves receive data in a push fashion.
+#
+# Both the hard or the soft limit can be disabled just setting it to zero.
+client-output-buffer-limit normal 0 0 0
+client-output-buffer-limit slave 256mb 64mb 60
+client-output-buffer-limit pubsub 32mb 8mb 60
+
################################## 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
+# 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.
#