Cache_redis, save() method: An optimization, moving sRemove call.
diff --git a/system/libraries/Cache/drivers/Cache_redis.php b/system/libraries/Cache/drivers/Cache_redis.php
index b5387c0..26de61d 100644
--- a/system/libraries/Cache/drivers/Cache_redis.php
+++ b/system/libraries/Cache/drivers/Cache_redis.php
@@ -114,9 +114,8 @@
 			if (($index_key = array_search($id, $this->_serialized, TRUE)) !== FALSE)
 			{
 				unset($this->_serialized[$index_key]);
+				$this->_redis->sRemove('_ci_redis_serialized', $id);
 			}
-
-			$this->_redis->sRemove('_ci_redis_serialized', $id);
 		}
 
 		return ($ttl)