diff --git a/include/libtorrent/session_settings.hpp b/include/libtorrent/session_settings.hpp
index fa1437f68..c71337004 100644
--- a/include/libtorrent/session_settings.hpp
+++ b/include/libtorrent/session_settings.hpp
@@ -183,7 +183,7 @@ namespace libtorrent
 			, max_sparse_regions(0)
 #endif
 #ifndef TORRENT_DISABLE_MLOCK
-			, lock_disk_cache(true)
+			, lock_disk_cache(false)
 #endif
 			, max_rejects(50)
 			, recv_socket_buffer_size(0)