diff --git a/tikv-client/scripts/proto.sh b/tikv-client/scripts/proto.sh
index 23c668ca7b..fb92ee7f31 100755
--- a/tikv-client/scripts/proto.sh
+++ b/tikv-client/scripts/proto.sh
@@ -18,7 +18,7 @@ CURRENT_DIR=`pwd`
 TISPARK_HOME="$(cd "`dirname "$0"`"/../..; pwd)"
 cd $TISPARK_HOME/tikv-client
 
-kvproto_hash=6ed99a08e262d8a32d6355dcba91cf99cb92074a
+kvproto_hash=62630088ebc1aabcba3038ede6e775d89d38c98b
 
 raft_rs_hash=b9891b673573fad77ebcf9bbe0969cf945841926
 
diff --git a/tikv-client/src/main/java/com/pingcap/tikv/TiConfiguration.java b/tikv-client/src/main/java/com/pingcap/tikv/TiConfiguration.java
index f74a532206..3d90486e8c 100644
--- a/tikv-client/src/main/java/com/pingcap/tikv/TiConfiguration.java
+++ b/tikv-client/src/main/java/com/pingcap/tikv/TiConfiguration.java
@@ -34,7 +34,7 @@ public class TiConfiguration implements Serializable {
   private static final DateTimeZone DEF_TIMEZONE = Converter.getLocalTimezone();
   private static final int DEF_TIMEOUT = 10;
   private static final TimeUnit DEF_TIMEOUT_UNIT = TimeUnit.MINUTES;
-  private static final int DEF_SCAN_BATCH_SIZE = 10480;
+  private static final int DEF_SCAN_BATCH_SIZE = 10240;
   private static final boolean DEF_IGNORE_TRUNCATE = true;
   private static final boolean DEF_TRUNCATE_AS_WARNING = false;
   private static final int DEF_MAX_FRAME_SIZE = 2147483647; // 2 GB
diff --git a/tikv-client/src/main/java/com/pingcap/tikv/operation/KVErrorHandler.java b/tikv-client/src/main/java/com/pingcap/tikv/operation/KVErrorHandler.java
index 526e6056c2..df4b271be5 100644
--- a/tikv-client/src/main/java/com/pingcap/tikv/operation/KVErrorHandler.java
+++ b/tikv-client/src/main/java/com/pingcap/tikv/operation/KVErrorHandler.java
@@ -320,20 +320,22 @@ public boolean handleResponseError(BackOffer backOffer, RespT resp) {
     boolean retry = false;
 
     if (resp instanceof ScanResponse) {
-      List<KvPair> kvPairs = ((ScanResponse) resp).getPairsList();
-      List<Lock> locks = new ArrayList<>();
-      for (KvPair kvPair : kvPairs) {
-        if (kvPair.hasError()) {
-          Lock lock = AbstractLockResolverClient.extractLockFromKeyErr(kvPair.getError());
-          locks.add(lock);
+      if (((ScanResponse) resp).hasError()) {
+        List<KvPair> kvPairs = ((ScanResponse) resp).getPairsList();
+        List<Lock> locks = new ArrayList<>();
+        for (KvPair kvPair : kvPairs) {
+          if (kvPair.hasError()) {
+            Lock lock = AbstractLockResolverClient.extractLockFromKeyErr(kvPair.getError());
+            locks.add(lock);
+          }
         }
-      }
-      if (!locks.isEmpty()) {
-        try {
-          resolveLocks(backOffer, locks);
-          retry = true;
-        } catch (KeyException e) {
-          logger.warn("Unable to handle KeyExceptions other than LockException", e);
+        if (!locks.isEmpty()) {
+          try {
+            resolveLocks(backOffer, locks);
+            retry = true;
+          } catch (KeyException e) {
+            logger.warn("Unable to handle KeyExceptions other than LockException", e);
+          }
         }
       }
     } else {
diff --git a/tikv-client/src/main/java/com/pingcap/tikv/operation/iterator/ConcreteScanIterator.java b/tikv-client/src/main/java/com/pingcap/tikv/operation/iterator/ConcreteScanIterator.java
index 44cfb586e0..d8c6d10390 100644
--- a/tikv-client/src/main/java/com/pingcap/tikv/operation/iterator/ConcreteScanIterator.java
+++ b/tikv-client/src/main/java/com/pingcap/tikv/operation/iterator/ConcreteScanIterator.java
@@ -62,9 +62,9 @@ TiRegion loadCurrentRegionToCache() throws GrpcException {
         if (limit <= 0) {
           currentCache = null;
         } else {
+          int scanLimit = Math.min(limit, conf.getScanBatchSize());
           try {
-            int scanSize = Math.min(limit, conf.getScanBatchSize());
-            currentCache = client.scan(backOffer, startKey, scanSize, version);
+            currentCache = client.scan(backOffer, startKey, scanLimit, version);
           } catch (final TiKVException e) {
             backOffer.doBackOff(BackOffFunction.BackOffFuncType.BoRegionMiss, e);
             continue;