Better system for additional commands replication.

[redis.git] / redis.conf

diff --git a/redis.conf b/redis.conf
index ad0c96e90f2a9817b22fbbb3ab84d3795826ea7a..4760f291481d9d784e70e088c8c05e33e102ecd5 100644 (file)
--- a/redis.conf
+++ b/redis.conf
@@ -201,21 +201,27 @@ slave-serve-stale-data yes
 # maxclients 10000
 
 # Don't use more memory than the specified amount of bytes.
 # 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>
 
 #
 # maxmemory <bytes>
 


@@ -446,6 +452,43 @@ zset-max-ziplist-value 64
 # want to free memory asap when possible.
 activerehashing yes
 
 # 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
 ################################## INCLUDES ###################################
 
 # Include one or more other config files here.  This is useful if you