[Improvement] change default config (#350)

diff --git a/flink-doris-connector/src/main/java/org/apache/doris/flink/cfg/ConfigurationOptions.java b/flink-doris-connector/src/main/java/org/apache/doris/flink/cfg/ConfigurationOptions.java
index ff6ad47..4a3f70b 100644
--- a/flink-doris-connector/src/main/java/org/apache/doris/flink/cfg/ConfigurationOptions.java
+++ b/flink-doris-connector/src/main/java/org/apache/doris/flink/cfg/ConfigurationOptions.java
@@ -35,18 +35,18 @@
     Integer DORIS_REQUEST_RETRIES_DEFAULT = 3;
     Integer DORIS_REQUEST_CONNECT_TIMEOUT_MS_DEFAULT = 30 * 1000;
     Integer DORIS_REQUEST_READ_TIMEOUT_MS_DEFAULT = 30 * 1000;
-    Integer DORIS_REQUEST_QUERY_TIMEOUT_S_DEFAULT = 3600;
+    Integer DORIS_REQUEST_QUERY_TIMEOUT_S_DEFAULT = 21600;
 
     String DORIS_TABLET_SIZE = "doris.request.tablet.size";
-    Integer DORIS_TABLET_SIZE_DEFAULT = Integer.MAX_VALUE;
+    Integer DORIS_TABLET_SIZE_DEFAULT = 1;
     Integer DORIS_TABLET_SIZE_MIN = 1;
 
     String DORIS_BATCH_SIZE = "doris.batch.size";
     Integer DORIS_BATCH_SIZE_DEFAULT = 1024;
 
     String DORIS_EXEC_MEM_LIMIT = "doris.exec.mem.limit";
-    Long DORIS_EXEC_MEM_LIMIT_DEFAULT = 2147483648L;
-    String DORIS_EXEC_MEM_LIMIT_DEFAULT_STR = "2048mb";
+    Long DORIS_EXEC_MEM_LIMIT_DEFAULT = 8589934592L;
+    String DORIS_EXEC_MEM_LIMIT_DEFAULT_STR = "8192mb";
     String DORIS_DESERIALIZE_ARROW_ASYNC = "doris.deserialize.arrow.async";
     Boolean DORIS_DESERIALIZE_ARROW_ASYNC_DEFAULT = false;
     String DORIS_DESERIALIZE_QUEUE_SIZE = "doris.deserialize.queue.size";
diff --git a/flink-doris-connector/src/main/java/org/apache/doris/flink/serialization/RowBatch.java b/flink-doris-connector/src/main/java/org/apache/doris/flink/serialization/RowBatch.java
index 486cbd6..c0c2aec 100644
--- a/flink-doris-connector/src/main/java/org/apache/doris/flink/serialization/RowBatch.java
+++ b/flink-doris-connector/src/main/java/org/apache/doris/flink/serialization/RowBatch.java
@@ -117,9 +117,9 @@
                 fieldVectors = root.getFieldVectors();
                 if (fieldVectors.size() > schema.size()) {
                     logger.error(
-                            "Schema size '{}' is not equal to arrow field size '{}'.",
-                            fieldVectors.size(),
-                            schema.size());
+                            "Data schema size '{}' should not be bigger than arrow field size '{}'",
+                            schema.size(),
+                            fieldVectors.size());
                     throw new DorisException(
                             "Load Doris data failed, schema size of fetch data is wrong.");
                 }