MapDBLog: disable LRU

Change-Id: I02668ff24198f4081b9e8ffd34b7e9d43080956a
diff --git a/core/store/dist/src/main/java/org/onlab/onos/store/service/impl/MapDBLog.java b/core/store/dist/src/main/java/org/onlab/onos/store/service/impl/MapDBLog.java
index c2e3d8f..aac1c87 100644
--- a/core/store/dist/src/main/java/org/onlab/onos/store/service/impl/MapDBLog.java
+++ b/core/store/dist/src/main/java/org/onlab/onos/store/service/impl/MapDBLog.java
@@ -52,7 +52,6 @@
     public void open() throws IOException {
         txMaker = DBMaker
                 .newFileDB(dbFile)
-                .cacheLRUEnable()
                 .cacheSize(cacheSize)
                 .makeTxMaker();
     }