diff --git a/client/src/main/java/org/apache/rocketmq/client/consumer/DefaultMQPushConsumer.java b/client/src/main/java/org/apache/rocketmq/client/consumer/DefaultMQPushConsumer.java
index 7fb6dc0999..8e1c8d15af 100644
--- a/client/src/main/java/org/apache/rocketmq/client/consumer/DefaultMQPushConsumer.java
+++ b/client/src/main/java/org/apache/rocketmq/client/consumer/DefaultMQPushConsumer.java
@@ -640,7 +640,7 @@ public class DefaultMQPushConsumer extends ClientConfig implements MQPushConsume
      */
     @Deprecated
     public void setSubscription(Map<String, String> subscription) {
-        Map<String, String> subscriptionWithNamespace = new HashMap<String, String>();
+        Map<String, String> subscriptionWithNamespace = new HashMap<String, String>(subscription.size(), 1);
         for (Entry<String, String> topicEntry : subscription.entrySet()) {
             subscriptionWithNamespace.put(withNamespace(topicEntry.getKey()), topicEntry.getValue());
         }
diff --git a/client/src/main/java/org/apache/rocketmq/client/consumer/store/LocalFileOffsetStore.java b/client/src/main/java/org/apache/rocketmq/client/consumer/store/LocalFileOffsetStore.java
index d380ba058a..f949b75a81 100644
--- a/client/src/main/java/org/apache/rocketmq/client/consumer/store/LocalFileOffsetStore.java
+++ b/client/src/main/java/org/apache/rocketmq/client/consumer/store/LocalFileOffsetStore.java
@@ -169,7 +169,7 @@ public class LocalFileOffsetStore implements OffsetStore {
 
     @Override
     public Map<MessageQueue, Long> cloneOffsetTable(String topic) {
-        Map<MessageQueue, Long> cloneOffsetTable = new HashMap<MessageQueue, Long>();
+        Map<MessageQueue, Long> cloneOffsetTable = new HashMap<MessageQueue, Long>(this.offsetTable.size(), 1);
         for (Map.Entry<MessageQueue, AtomicLong> entry : this.offsetTable.entrySet()) {
             MessageQueue mq = entry.getKey();
             if (!UtilAll.isBlank(topic) && !topic.equals(mq.getTopic())) {
diff --git a/client/src/main/java/org/apache/rocketmq/client/consumer/store/RemoteBrokerOffsetStore.java b/client/src/main/java/org/apache/rocketmq/client/consumer/store/RemoteBrokerOffsetStore.java
index 15b5becfd4..409ceab954 100644
--- a/client/src/main/java/org/apache/rocketmq/client/consumer/store/RemoteBrokerOffsetStore.java
+++ b/client/src/main/java/org/apache/rocketmq/client/consumer/store/RemoteBrokerOffsetStore.java
@@ -174,7 +174,7 @@ public class RemoteBrokerOffsetStore implements OffsetStore {
 
     @Override
     public Map<MessageQueue, Long> cloneOffsetTable(String topic) {
-        Map<MessageQueue, Long> cloneOffsetTable = new HashMap<MessageQueue, Long>();
+        Map<MessageQueue, Long> cloneOffsetTable = new HashMap<MessageQueue, Long>(this.offsetTable.size(), 1);
         for (Map.Entry<MessageQueue, AtomicLong> entry : this.offsetTable.entrySet()) {
             MessageQueue mq = entry.getKey();
             if (!UtilAll.isBlank(topic) && !topic.equals(mq.getTopic())) {
diff --git a/client/src/main/java/org/apache/rocketmq/client/impl/MQClientAPIImpl.java b/client/src/main/java/org/apache/rocketmq/client/impl/MQClientAPIImpl.java
index be70d9f5fa..f2d01897c8 100644
--- a/client/src/main/java/org/apache/rocketmq/client/impl/MQClientAPIImpl.java
+++ b/client/src/main/java/org/apache/rocketmq/client/impl/MQClientAPIImpl.java
@@ -388,7 +388,7 @@ public class MQClientAPIImpl {
                 clusterAclVersionInfo.setBrokerAddr(responseHeader.getBrokerAddr());
                 clusterAclVersionInfo.setAclConfigDataVersion(DataVersion.fromJson(responseHeader.getVersion(), DataVersion.class));
                 HashMap<String, Object> dataVersionMap = JSON.parseObject(responseHeader.getAllAclFileVersion(), HashMap.class);
-                Map<String, DataVersion> allAclConfigDataVersion = new HashMap<String, DataVersion>();
+                Map<String, DataVersion> allAclConfigDataVersion = new HashMap<String, DataVersion>(dataVersionMap.size(), 1);
                 for (Map.Entry<String, Object> entry : dataVersionMap.entrySet()) {
                     allAclConfigDataVersion.put(entry.getKey(),DataVersion.fromJson(JSON.toJSONString(entry.getValue()), DataVersion.class));
                 }
diff --git a/client/src/main/java/org/apache/rocketmq/client/impl/consumer/DefaultMQPushConsumerImpl.java b/client/src/main/java/org/apache/rocketmq/client/impl/consumer/DefaultMQPushConsumerImpl.java
index a338f7b681..31cd64c01e 100644
--- a/client/src/main/java/org/apache/rocketmq/client/impl/consumer/DefaultMQPushConsumerImpl.java
+++ b/client/src/main/java/org/apache/rocketmq/client/impl/consumer/DefaultMQPushConsumerImpl.java
@@ -28,6 +28,7 @@ import java.util.Properties;
 import java.util.Set;
 import java.util.concurrent.ConcurrentMap;
 
+import org.apache.commons.collections.CollectionUtils;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.rocketmq.client.QueryResult;
 import org.apache.rocketmq.client.Validators;
@@ -962,8 +963,8 @@ public class DefaultMQPushConsumerImpl implements MQConsumerInner {
         throws RemotingException, MQBrokerException, InterruptedException, MQClientException {
         for (String topic : rebalanceImpl.getSubscriptionInner().keySet()) {
             Set<MessageQueue> mqs = rebalanceImpl.getTopicSubscribeInfoTable().get(topic);
-            Map<MessageQueue, Long> offsetTable = new HashMap<MessageQueue, Long>();
-            if (mqs != null) {
+            if (CollectionUtils.isNotEmpty(mqs)) {
+                Map<MessageQueue, Long> offsetTable = new HashMap<MessageQueue, Long>(mqs.size(), 1);
                 for (MessageQueue mq : mqs) {
                     long offset = searchOffset(mq, timeStamp);
                     offsetTable.put(mq, offset);
diff --git a/client/src/main/java/org/apache/rocketmq/client/impl/consumer/RebalanceImpl.java b/client/src/main/java/org/apache/rocketmq/client/impl/consumer/RebalanceImpl.java
index 7677d8b685..f239d7946b 100644
--- a/client/src/main/java/org/apache/rocketmq/client/impl/consumer/RebalanceImpl.java
+++ b/client/src/main/java/org/apache/rocketmq/client/impl/consumer/RebalanceImpl.java
@@ -117,7 +117,7 @@ public abstract class RebalanceImpl {
     }
 
     private HashMap<String/* brokerName */, Set<MessageQueue>> buildProcessQueueTableByBrokerName() {
-        HashMap<String, Set<MessageQueue>> result = new HashMap<String, Set<MessageQueue>>();
+        HashMap<String, Set<MessageQueue>> result = new HashMap<String, Set<MessageQueue>>(this.processQueueTable.size(), 1);
         for (MessageQueue mq : this.processQueueTable.keySet()) {
             Set<MessageQueue> mqs = result.get(mq.getBrokerName());
             if (null == mqs) {
diff --git a/client/src/main/java/org/apache/rocketmq/client/impl/factory/MQClientInstance.java b/client/src/main/java/org/apache/rocketmq/client/impl/factory/MQClientInstance.java
index d5b90979e0..1ba3e32f3c 100644
--- a/client/src/main/java/org/apache/rocketmq/client/impl/factory/MQClientInstance.java
+++ b/client/src/main/java/org/apache/rocketmq/client/impl/factory/MQClientInstance.java
@@ -366,7 +366,7 @@ public class MQClientInstance {
      * @return newOffsetTable
      */
     public Map<MessageQueue, Long> parseOffsetTableFromBroker(Map<MessageQueue, Long> offsetTable, String namespace) {
-        HashMap<MessageQueue, Long> newOffsetTable = new HashMap<MessageQueue, Long>();
+        HashMap<MessageQueue, Long> newOffsetTable = new HashMap<MessageQueue, Long>(offsetTable.size(), 1);
         if (StringUtils.isNotEmpty(namespace)) {
             for (Entry<MessageQueue, Long> entry : offsetTable.entrySet()) {
                 MessageQueue queue = entry.getKey();
@@ -387,7 +387,7 @@ public class MQClientInstance {
         try {
             if (this.lockNamesrv.tryLock(LOCK_TIMEOUT_MILLIS, TimeUnit.MILLISECONDS))
                 try {
-                    ConcurrentHashMap<String, HashMap<Long, String>> updatedTable = new ConcurrentHashMap<String, HashMap<Long, String>>();
+                    ConcurrentHashMap<String, HashMap<Long, String>> updatedTable = new ConcurrentHashMap<String, HashMap<Long, String>>(this.brokerAddrTable.size(), 1);
 
                     Iterator<Entry<String, HashMap<Long, String>>> itBrokerTable = this.brokerAddrTable.entrySet().iterator();
                     while (itBrokerTable.hasNext()) {
@@ -395,7 +395,7 @@ public class MQClientInstance {
                         String brokerName = entry.getKey();
                         HashMap<Long, String> oneTable = entry.getValue();
 
-                        HashMap<Long, String> cloneAddrTable = new HashMap<Long, String>();
+                        HashMap<Long, String> cloneAddrTable = new HashMap<Long, String>(oneTable.size(), 1);
                         cloneAddrTable.putAll(oneTable);
 
                         Iterator<Entry<Long, String>> it = cloneAddrTable.entrySet().iterator();
diff --git a/client/src/main/java/org/apache/rocketmq/client/trace/AsyncTraceDispatcher.java b/client/src/main/java/org/apache/rocketmq/client/trace/AsyncTraceDispatcher.java
index 86153f5263..7652ee0e50 100644
--- a/client/src/main/java/org/apache/rocketmq/client/trace/AsyncTraceDispatcher.java
+++ b/client/src/main/java/org/apache/rocketmq/client/trace/AsyncTraceDispatcher.java
@@ -330,6 +330,7 @@ public class AsyncTraceDispatcher implements TraceDispatcher {
                 traceExecutor.submit(asyncDataSendTask);
 
                 this.clear();
+
             }
         }