Remove unnecessary synchronization for IoTConsensus memeory management (#16049)

Author: jt2594838

iotdb-core/consensus/src/main/java/org/apache/iotdb/consensus/iot/logdispatcher/IoTConsensusMemoryManager.java

@@ -42,13 +42,11 @@ private IoTConsensusMemoryManager() {
   }
 
   public boolean reserve(IndexedConsensusRequest request, boolean fromQueue) {
-    synchronized (request) {
-      long prevRef = request.incRef();
-      if (prevRef == 0) {
-        return reserve(request.getMemorySize(), fromQueue);
-      } else {
-        return true;
-      }
+    long prevRef = request.incRef();
+    if (prevRef == 0) {
+      return reserve(request.getMemorySize(), fromQueue);
+    } else {
+      return true;
     }
   }
 
@@ -68,11 +66,9 @@ public boolean reserve(long size, boolean fromQueue) {
   }
 
   public void free(IndexedConsensusRequest request, boolean fromQueue) {
-    synchronized (request) {
-      long prevRef = request.decRef();
-      if (prevRef == 0) {
-        free(request.getMemorySize(), fromQueue);
-      }
+    long prevRef = request.decRef();
+    if (prevRef == 1) {
+      free(request.getMemorySize(), fromQueue);
     }
   }
 

iotdb-core/consensus/src/main/java/org/apache/iotdb/consensus/iot/logdispatcher/LogDispatcher.java

@@ -322,22 +322,18 @@ private void processStopped() {
       }
       long requestSize = 0;
       for (IndexedConsensusRequest indexedConsensusRequest : pendingEntries) {
-        synchronized (indexedConsensusRequest) {
-          long prevRef = indexedConsensusRequest.decRef();
-          if (prevRef == 1) {
-            requestSize += indexedConsensusRequest.getMemorySize();
-          }
+        long prevRef = indexedConsensusRequest.decRef();
+        if (prevRef == 1) {
+          requestSize += indexedConsensusRequest.getMemorySize();
         }
       }
       pendingEntries.clear();
       iotConsensusMemoryManager.free(requestSize, true);
       requestSize = 0;
       for (IndexedConsensusRequest indexedConsensusRequest : bufferedEntries) {
-        synchronized (indexedConsensusRequest) {
-          long prevRef = indexedConsensusRequest.decRef();
-          if (prevRef == 1) {
-            requestSize += indexedConsensusRequest.getMemorySize();
-          }
+        long prevRef = indexedConsensusRequest.decRef();
+        if (prevRef == 1) {
+          requestSize += indexedConsensusRequest.getMemorySize();
         }
       }
       iotConsensusMemoryManager.free(requestSize, true);