(iotdb) branch object_type updated: Limit the return size for client instead of always using fetchSize

[jackietien]

This is an automated email from the ASF dual-hosted git repository.

jackietien pushed a commit to branch object_type
in repository https://gitbox.apache.org/repos/asf/iotdb.git


The following commit(s) were added to refs/heads/object_type by this push:
     new 9d6a25301cb Limit the return size for client instead of always using 
fetchSize
9d6a25301cb is described below

commit 9d6a25301cb17fbf9d5ee12c5dc0ad06c0542afa
Author: JackieTien97 <jackietie...@gmail.com>
AuthorDate: Sat Jul 12 10:30:06 2025 +0800

    Limit the return size for client instead of always using fetchSize
---
 .../src/main/java/org/apache/iotdb/db/utils/QueryDataSetUtils.java | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git 
a/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/utils/QueryDataSetUtils.java
 
b/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/utils/QueryDataSetUtils.java
index fed80815f69..6220623dd3b 100644
--- 
a/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/utils/QueryDataSetUtils.java
+++ 
b/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/utils/QueryDataSetUtils.java
@@ -51,6 +51,9 @@ public class QueryDataSetUtils {
 
   private static final TSFileConfig TSFLE_CONFIG = 
TSFileDescriptor.getInstance().getConfig();
 
+  // default return 8 MB each time
+  private static final long MAX_RETURN_SIZE = 8 * 1024 * 1024;
+
   private QueryDataSetUtils() {}
 
   public static Pair<TSQueryDataSet, Boolean> convertTsBlockByFetchSize(
@@ -616,8 +619,9 @@ public class QueryDataSetUtils {
       IQueryExecution queryExecution, int fetchSize) throws IoTDBException {
     fetchSize = fetchSize > 0 ? fetchSize : 
TSFLE_CONFIG.getMaxTsBlockLineNumber();
     int rowCount = 0;
+    long memorySize = 0;
     List<ByteBuffer> res = new ArrayList<>();
-    while (rowCount < fetchSize) {
+    while (rowCount < fetchSize && memorySize < MAX_RETURN_SIZE) {
       Optional<ByteBuffer> optionalByteBuffer = 
queryExecution.getByteBufferBatchResult();
       if (!optionalByteBuffer.isPresent()) {
         break;
@@ -634,6 +638,7 @@ public class QueryDataSetUtils {
         res.add(byteBuffer);
       }
       rowCount += positionCount;
+      memorySize += byteBuffer.limit();
     }
     return new Pair<>(res, !queryExecution.hasNextResult());
   }