diff --git a/server/src/main/java/org/apache/iotdb/db/engine/memtable/AbstractMemTable.java b/server/src/main/java/org/apache/iotdb/db/engine/memtable/AbstractMemTable.java
index 0ddc384bf4857..e97f5c00bd6b6 100644
--- a/server/src/main/java/org/apache/iotdb/db/engine/memtable/AbstractMemTable.java
+++ b/server/src/main/java/org/apache/iotdb/db/engine/memtable/AbstractMemTable.java
@@ -116,11 +116,11 @@ public void insert(InsertRowPlan insertRowPlan) {
     updatePlanIndexes(insertRowPlan.getIndex());
     for (int i = 0; i < insertRowPlan.getValues().length; i++) {
 
-      if (insertRowPlan.getValues()[i] == null) {
+      Object value = insertRowPlan.getValues()[i];
+      if (value == null) {
         continue;
       }
 
-      Object value = insertRowPlan.getValues()[i];
       memSize += MemUtils
           .getRecordSize(insertRowPlan.getMeasurementMNodes()[i].getSchema().getType(), value,
               disableMemControl);
diff --git a/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/StorageGroupProcessor.java b/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/StorageGroupProcessor.java
index 62c7607361a46..955deb4aabe8e 100755
--- a/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/StorageGroupProcessor.java
+++ b/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/StorageGroupProcessor.java
@@ -973,7 +973,8 @@ private TsFileProcessor getOrCreateTsFileProcessorIntern(long timeRangeId,
     // we have to ensure only one thread can change workSequenceTsFileProcessors
     writeLock();
     try {
-      if (!tsFileProcessorTreeMap.containsKey(timeRangeId)) {
+      res = tsFileProcessorTreeMap.get(timeRangeId);
+      if (res == null) {
         // we have to remove oldest processor to control the num of the memtables
         // TODO: use a method to control the number of memtables
         if (tsFileProcessorTreeMap.size()
@@ -992,8 +993,6 @@ private TsFileProcessor getOrCreateTsFileProcessorIntern(long timeRangeId,
         tsFileProcessorTreeMap.put(timeRangeId, newProcessor);
         tsFileManagement.add(newProcessor.getTsFileResource(), sequence);
         res = newProcessor;
-      } else {
-        res = tsFileProcessorTreeMap.get(timeRangeId);
       }
 
     } finally {