[ISSUE #6940] change dataReadAheadEnable default to false (#6944)

* [ISSUE #6390] Add break to the exception of WHEEL_TIMER_NOT_ENABLE.

* fix broker start fail if mapped file size is 0

* log

* only delete the last empty file

* change dataReadAheadEnable default to true

store/src/main/java/org/apache/rocketmq/store/config/MessageStoreConfig.java

@@ -381,7 +381,7 @@ public class MessageStoreConfig {
 
     private boolean coldDataFlowControlEnable = false;
     private boolean coldDataScanEnable = false;
-    private boolean dataReadAheadEnable = false;
+    private boolean dataReadAheadEnable = true;
     private int timerColdDataCheckIntervalMs = 60 * 1000;
     private int sampleSteps = 32;
     private int accessMessageInMemoryHotRatio = 26;