Pipe: Fix the problem that the Pipe memory block fails to call the Wait function (#15687)

Author: luoluoyuyu

iotdb-core/datanode/src/main/java/org/apache/iotdb/db/pipe/connector/payload/evolvable/batch/PipeTabletEventBatch.java

@@ -60,10 +60,9 @@ protected PipeTabletEventBatch(final int maxDelayInMs, final long requestMaxBatc
 
     // limit in buffer size
     this.allocatedMemoryBlock =
-        pipeModelFixedMemoryBlock =
-            PipeDataNodeResourceManager.memory()
-                .forceAllocateForModelFixedMemoryBlock(
-                    requestMaxBatchSizeInBytes, PipeMemoryBlockType.BATCH);
+        PipeDataNodeResourceManager.memory()
+            .forceAllocateForModelFixedMemoryBlock(
+                requestMaxBatchSizeInBytes, PipeMemoryBlockType.BATCH);
 
     if (getMaxBatchSizeInBytes() != requestMaxBatchSizeInBytes) {
       LOGGER.info(

iotdb-core/datanode/src/main/java/org/apache/iotdb/db/pipe/resource/memory/PipeMemoryManager.java

@@ -262,11 +262,11 @@ public PipeModelFixedMemoryBlock forceAllocateForModelFixedMemoryBlock(
       }
     }
 
-    if (getFreeMemorySizeInBytes() < fixedSizeInBytes) {
-      return (PipeModelFixedMemoryBlock) forceAllocateWithRetry(getFreeMemorySizeInBytes(), type);
-    }
-
     synchronized (this) {
+      if (getFreeMemorySizeInBytes() < fixedSizeInBytes) {
+        return (PipeModelFixedMemoryBlock) forceAllocateWithRetry(getFreeMemorySizeInBytes(), type);
+      }
+
       return (PipeModelFixedMemoryBlock) forceAllocateWithRetry(fixedSizeInBytes, type);
     }
   }