lzf compression switched off by default now, with config file option to enable it in redis.conf

redis.c

@@ -301,6 +301,7 @@ struct redisServer {
     char *appendfilename;
     char *requirepass;
     int shareobjects;
+    int rdbcompression;
     /* Replication related */
     int isslave;
     char *masterauth;
@@ -1141,6 +1142,7 @@ static void initServerConfig() {
     server.appendfilename = "appendonly.aof";
     server.requirepass = NULL;
     server.shareobjects = 0;
+    server.rdbcompression = 0;
     server.sharingpoolsize = 1024;
     server.maxclients = 0;
     server.maxmemory = 0;
@@ -1341,6 +1343,10 @@ static void loadServerConfig(char *filename) {
             if ((server.shareobjects = yesnotoi(argv[1])) == -1) {
                 err = "argument must be 'yes' or 'no'"; goto loaderr;
             }
+        } else if (!strcasecmp(argv[0],"rdbcompression") && argc == 2) {
+            if ((server.rdbcompression = yesnotoi(argv[1])) == -1) {
+                err = "argument must be 'yes' or 'no'"; goto loaderr;
+            }
         } else if (!strcasecmp(argv[0],"shareobjectspoolsize") && argc == 2) {
             server.sharingpoolsize = atoi(argv[1]);
             if (server.sharingpoolsize < 1) {
@@ -2488,7 +2494,7 @@ static int rdbSaveStringObjectRaw(FILE *fp, robj *obj) {
 
     /* Try LZF compression - under 20 bytes it's unable to compress even
      * aaaaaaaaaaaaaaaaaa so skip it */
-    if (len > 20) {
+    if (server.rdbcompression && len > 20) {
         int retval;
 
         retval = rdbSaveLzfStringObject(fp,obj);

redis.conf

@@ -19,28 +19,6 @@ port 6379
 # Close the connection after a client is idle for N seconds (0 to disable)
 timeout 300
 
-# Save the DB on disk:
-#
-#   save <seconds> <changes>
-#
-#   Will save the DB if both the given number of seconds and the given
-#   number of write operations against the DB occurred.
-#
-#   In the example below the behaviour will be to save:
-#   after 900 sec (15 min) if at least 1 key changed
-#   after 300 sec (5 min) if at least 10 keys changed
-#   after 60 sec if at least 10000 keys changed
-save 900 1
-save 300 10
-save 60 10000
-
-# 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.
-dir ./
-
 # Set server verbosity to 'debug'
 # it can be one of:
 # debug (a lot of information, useful for development/testing)
@@ -58,6 +36,36 @@ logfile stdout
 # dbid is a number between 0 and 'databases'-1
 databases 16
 
+################################ SNAPSHOTTING  #################################
+#
+# Save the DB on disk:
+#
+#   save <seconds> <changes>
+#
+#   Will save the DB if both the given number of seconds and the given
+#   number of write operations against the DB occurred.
+#
+#   In the example below the behaviour will be to save:
+#   after 900 sec (15 min) if at least 1 key changed
+#   after 300 sec (5 min) if at least 10 keys changed
+#   after 60 sec if at least 10000 keys changed
+save 900 1
+save 300 10
+save 60 10000
+
+# Compress string objects using LZF when dump .rdb databases?
+# For default that's set to 'no' because uses too much CPU time.
+# You want to switch this to 'yes' only if you have a lot of very compressible
+# data inside your dataset and are using replication.
+rdbcompression no
+
+# 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.
+dir ./
+
 ################################# REPLICATION #################################
 
 # Master-Slave replication. Use slaveof to make a Redis instance a copy of