Default LRU samples is now 5.

redis.conf

@@ -419,12 +419,15 @@ slave-priority 100
 # maxmemory-policy volatile-lru
 
 # LRU and minimal TTL algorithms are not precise algorithms but approximated
-# algorithms (in order to save memory), so you can select as well the sample
-# size to check. For instance for default Redis will check three keys and
-# pick the one that was used less recently, you can change the sample size
-# using the following configuration directive.
+# algorithms (in order to save memory), so you can tune it for speed or
+# accuracy. For default Redis will check five keys and pick the one that was
+# used less recently, you can change the sample size using the following
+# configuration directive.
 #
-# maxmemory-samples 3
+# The default of 5 produces good enough results. 10 Approximates very closely
+# true LRU but costs a bit more CPU. 3 is very fast but not very accurate.
+#
+# maxmemory-samples 5
 
 ############################## APPEND ONLY MODE ###############################
 

src/redis.h

@@ -113,7 +113,7 @@
 #define REDIS_DEFAULT_SLAVE_READ_ONLY 1
 #define REDIS_DEFAULT_REPL_DISABLE_TCP_NODELAY 0
 #define REDIS_DEFAULT_MAXMEMORY 0
-#define REDIS_DEFAULT_MAXMEMORY_SAMPLES 3
+#define REDIS_DEFAULT_MAXMEMORY_SAMPLES 5
 #define REDIS_DEFAULT_AOF_FILENAME "appendonly.aof"
 #define REDIS_DEFAULT_AOF_NO_FSYNC_ON_REWRITE 0
 #define REDIS_DEFAULT_ACTIVE_REHASHING 1