resolve the deadlock when schema change (apache#124)

Lchangliang · Jun 9, 2022 · 8b2f994 · 8b2f994
1 parent 9927468
commit 8b2f994
Showing 1 changed file with 5 additions and 4 deletions.
diff --git a/be/src/olap/schema_change.cpp b/be/src/olap/schema_change.cpp
@@ -1436,6 +1436,7 @@ Status SchemaChangeHandler::_do_process_alter_tablet_v2(const TAlterTabletReqV2&
     // delete handlers for new tablet
     DeleteHandler delete_handler;
     std::vector<ColumnId> return_columns;
+    auto base_tablet_schema = base_tablet->tablet_schema();
 
     // begin to find deltas to convert from base tablet to new tablet so that
     // obtain base tablet and new tablet's push lock and header write lock to prevent loading data
@@ -1446,7 +1447,7 @@ Status SchemaChangeHandler::_do_process_alter_tablet_v2(const TAlterTabletReqV2&
         std::lock_guard<std::shared_mutex> new_tablet_wlock(new_tablet->get_header_lock());
         // check if the tablet has alter task
         // if it has alter task, it means it is under old alter process
-        size_t num_cols = base_tablet->tablet_schema().num_columns();
+        size_t num_cols = base_tablet_schema.num_columns();
         return_columns.resize(num_cols);
         for (int i = 0; i < num_cols; ++i) {
             return_columns[i] = i;
@@ -1456,7 +1457,7 @@ Status SchemaChangeHandler::_do_process_alter_tablet_v2(const TAlterTabletReqV2&
         // with rs_readers
         RowsetReaderContext reader_context;
         reader_context.reader_type = READER_ALTER_TABLE;
-        reader_context.tablet_schema = &base_tablet->tablet_schema();
+        reader_context.tablet_schema = &base_tablet_schema;
         reader_context.need_ordered_result = true;
         reader_context.delete_handler = &delete_handler;
         reader_context.return_columns = &return_columns;
@@ -1528,8 +1529,8 @@ Status SchemaChangeHandler::_do_process_alter_tablet_v2(const TAlterTabletReqV2&
                 }
             }
 
-            res = delete_handler.init(base_tablet->tablet_schema(),
-                                      base_tablet->delete_predicates(), end_version);
+            res = delete_handler.init(base_tablet_schema, base_tablet->delete_predicates(),
+                                      end_version);
             if (!res.ok()) {
                 LOG(WARNING) << "init delete handler failed. base_tablet="
                              << base_tablet->full_name() << ", end_version=" << end_version;