diff --git a/src/rootserver/ddl_task/ob_column_redefinition_task.h b/src/rootserver/ddl_task/ob_column_redefinition_task.h
index 0fe2d99b4f..d2c6b3141d 100644
--- a/src/rootserver/ddl_task/ob_column_redefinition_task.h
+++ b/src/rootserver/ddl_task/ob_column_redefinition_task.h
@@ -51,6 +51,8 @@ public:
   virtual bool support_longops_monitoring() const { return true; }
   virtual void flt_set_task_span_tag() const override;
   virtual void flt_set_status_span_tag() const override;
+  INHERIT_TO_STRING_KV("ObDDLRedefinitionTask", ObDDLRedefinitionTask,
+      K(has_rebuild_index_), K(has_rebuild_constraint_), K(has_rebuild_foreign_key_), K(is_sstable_complete_task_submitted_));
 private:
   int wait_data_complement(const share::ObDDLTaskStatus next_task_status);
   int send_build_single_replica_request();
diff --git a/src/rootserver/ddl_task/ob_ddl_redefinition_task.h b/src/rootserver/ddl_task/ob_ddl_redefinition_task.h
index 9f5bf0e0e3..08b1dbc3d8 100644
--- a/src/rootserver/ddl_task/ob_ddl_redefinition_task.h
+++ b/src/rootserver/ddl_task/ob_ddl_redefinition_task.h
@@ -127,6 +127,11 @@ public:
   virtual void flt_set_status_span_tag() const = 0;
   virtual int cleanup_impl() override;
   int try_reap_old_replica_build_task();
+  INHERIT_TO_STRING_KV("ObDDLTask", ObDDLTask,
+      K(wait_trans_ctx_), K(sync_tablet_autoinc_seq_ctx_), K(build_replica_request_time_),
+      K(complete_sstable_job_ret_code_), K(snapshot_held_), K(has_synced_autoincrement_),
+      K(has_synced_stats_info_), K(update_autoinc_job_ret_code_), K(update_autoinc_job_time_),
+      K(check_table_empty_job_ret_code_), K(check_table_empty_job_time_));
 protected:
   int prepare(const share::ObDDLTaskStatus next_task_status);
   int lock_table(const share::ObDDLTaskStatus next_task_status);
diff --git a/src/rootserver/ddl_task/ob_ddl_scheduler.cpp b/src/rootserver/ddl_task/ob_ddl_scheduler.cpp
index 76785ffd0e..38e8b49950 100644
--- a/src/rootserver/ddl_task/ob_ddl_scheduler.cpp
+++ b/src/rootserver/ddl_task/ob_ddl_scheduler.cpp
@@ -2001,7 +2001,6 @@ int ObDDLScheduler::on_column_checksum_calc_reply(
     const int ret_code)
 {
   int ret = OB_SUCCESS;
-  LOG_INFO("receive column checksum response", K(tablet_id), K(task_key), K(ret_code));
   if (OB_UNLIKELY(!is_inited_)) {
     ret = OB_NOT_INIT;
     LOG_WARN("not init", K(ret));
@@ -2020,6 +2019,7 @@ int ObDDLScheduler::on_column_checksum_calc_reply(
       }))) {
     LOG_WARN("failed to modify task", K(ret));
   }
+  LOG_INFO("receive column checksum response", K(ret), K(tablet_id), K(task_key), K(ret_code));
   return ret;
 }
 
diff --git a/src/rootserver/ddl_task/ob_ddl_task.cpp b/src/rootserver/ddl_task/ob_ddl_task.cpp
index 8c9888341b..b110556c49 100644
--- a/src/rootserver/ddl_task/ob_ddl_task.cpp
+++ b/src/rootserver/ddl_task/ob_ddl_task.cpp
@@ -1963,6 +1963,7 @@ int ObDDLWaitColumnChecksumCtx::init(
         || OB_INVALID_ID == tenant_id
         || OB_INVALID_ID == source_table_id
         || OB_INVALID_ID == target_table_id
+        || source_table_id == target_table_id
         || schema_version <= 0
         || snapshot_version <= 0
         || execution_id < 0
@@ -1972,11 +1973,15 @@ int ObDDLWaitColumnChecksumCtx::init(
         K(schema_version), K(snapshot_version), K(execution_id));
   } else {
     ObArray<ObTabletID> tablet_ids;
+    hash::ObHashSet<ObTabletID> tablet_set;
     PartitionColChecksumStat tmp_stat;
     const int64_t NEED_CALC_CHECKSUM_COUNT =  2;  // source table and target table
     tmp_stat.col_checksum_stat_ = CCS_INVALID;
     tmp_stat.execution_id_ = execution_id;
     tmp_stat.snapshot_ = -1;
+    if (OB_FAIL(tablet_set.create(1023))) {
+      LOG_WARN("create tablet set failed", K(ret));
+    }
     for (int64_t i = 0; OB_SUCC(ret) && i < NEED_CALC_CHECKSUM_COUNT; ++i) {
       const uint64_t cur_table_id =  0 == i ? source_table_id : target_table_id;
       tablet_ids.reset();
@@ -1992,7 +1997,9 @@ int ObDDLWaitColumnChecksumCtx::init(
         for (int64_t j = 0; OB_SUCC(ret) && j < tablet_ids.count(); ++j) {
           tmp_stat.tablet_id_ = tablet_ids.at(j);
           tmp_stat.table_id_ = cur_table_id;
-          if (OB_FAIL(stat_array_.push_back(tmp_stat))) {
+          if (OB_FAIL(tablet_set.set_refactored(tmp_stat.tablet_id_, 0/*not cover exists object*/))) {
+            LOG_WARN("put into set failed", K(ret), K(tmp_stat));
+          } else if (OB_FAIL(stat_array_.push_back(tmp_stat))) {
             LOG_WARN("push batck column checksum status array failed", K(ret), K(tmp_stat));
           }
         }
@@ -2032,6 +2039,8 @@ void ObDDLWaitColumnChecksumCtx::reset()
 int ObDDLWaitColumnChecksumCtx::try_wait(bool &is_column_checksum_ready)
 {
   is_column_checksum_ready = false;
+  int64_t success_count = 0;
+  int64_t send_succ_count = 0;
   int ret = OB_SUCCESS;
   if (OB_UNLIKELY(!is_inited_)) {
     ret = OB_NOT_INIT;
@@ -2041,7 +2050,6 @@ int ObDDLWaitColumnChecksumCtx::try_wait(bool &is_column_checksum_ready)
   } else {
     SpinRLockGuard guard(lock_);
     const int64_t check_count = stat_array_.count();
-    int64_t success_count = 0;
     for (int64_t i = 0; OB_SUCC(ret) && i < check_count; ++i) {
       const PartitionColChecksumStat &item = stat_array_.at(i);
       if (!item.is_valid()) {
@@ -2062,7 +2070,6 @@ int ObDDLWaitColumnChecksumCtx::try_wait(bool &is_column_checksum_ready)
     }
   }
   if (OB_SUCC(ret) && !is_calc_done_) {
-    int64_t send_succ_count = 0;
     if (0 != last_drive_ts_  && last_drive_ts_ + timeout_us_ < ObTimeUtility::current_time()) {
       // wait too long, refresh to retry send rpc
       if (OB_FAIL(refresh_zombie_task())) {
@@ -2077,6 +2084,9 @@ int ObDDLWaitColumnChecksumCtx::try_wait(bool &is_column_checksum_ready)
     }
   }
   is_column_checksum_ready = is_calc_done_;
+  if (REACH_TIME_INTERVAL(1000L * 1000L)) {
+    LOG_INFO("try wait checksum", K(ret), K(stat_array_.count()), K(success_count), K(send_succ_count));
+  }
   return ret;
 }
 
@@ -2110,6 +2120,18 @@ int ObDDLWaitColumnChecksumCtx::update_status(const common::ObTabletID &tablet_i
     if (!found) {
       ret = OB_ENTRY_NOT_EXIST;
       LOG_WARN("column_checksum_stat not found", K(ret), K(tablet_id));
+    } else {
+      int64_t last_found_pos = -1;
+      for (int64_t i = 0; i < stat_array_.count(); ++i) {
+        PartitionColChecksumStat &item = stat_array_.at(i);
+        if (tablet_id == item.tablet_id_) {
+          if (last_found_pos < 0) {
+            last_found_pos = i;
+          } else {
+            LOG_WARN("duplicated tablet id for validating checksum", K(tablet_id), K(last_found_pos), K(i));
+          }
+        }
+      }
     }
   }
   return ret;
diff --git a/src/rootserver/ddl_task/ob_ddl_task.h b/src/rootserver/ddl_task/ob_ddl_task.h
index 601e43f409..a8bfac4678 100644
--- a/src/rootserver/ddl_task/ob_ddl_task.h
+++ b/src/rootserver/ddl_task/ob_ddl_task.h
@@ -260,7 +260,7 @@ public:
   int try_wait(bool &is_trans_end, int64_t &snapshot_version, const bool need_wait_trans_end = true);
   transaction::ObTransID get_pending_tx_id() const { return pending_tx_id_; }
   TO_STRING_KV(K(is_inited_), K_(tenant_id), K(table_id_), K(is_trans_end_), K(wait_type_),
-      K(wait_version_), K_(pending_tx_id), K(tablet_ids_), K(snapshot_array_));
+      K(wait_version_), K_(pending_tx_id), K(tablet_ids_.count()), K(snapshot_array_.count()));
 
 private:
   static bool is_wait_trans_type_valid(const WaitTransType wait_trans_type);
diff --git a/src/rootserver/ddl_task/ob_table_redefinition_task.cpp b/src/rootserver/ddl_task/ob_table_redefinition_task.cpp
index 5f5c963bed..d56cbfbaf9 100644
--- a/src/rootserver/ddl_task/ob_table_redefinition_task.cpp
+++ b/src/rootserver/ddl_task/ob_table_redefinition_task.cpp
@@ -954,6 +954,8 @@ int ObTableRedefinitionTask::serialize_params_to_message(char *buf, const int64_
   } else if (OB_FAIL(serialization::encode_i8(buf, buf_len, pos, do_finish))) {
     LOG_WARN("fail to serialize is_do_finish");
   }
+  FLOG_INFO("serialize message for table redefinition", K(ret),
+      K(copy_indexes), K(copy_triggers), K(copy_constraints), K(copy_foreign_keys), K(ignore_errors), K(do_finish), K(*this));
   return ret;
 }
 
@@ -1002,6 +1004,8 @@ int ObTableRedefinitionTask::deserlize_params_from_message(const char *buf, cons
       is_do_finish_ = static_cast<bool>(do_finish);
     }
   }
+  FLOG_INFO("deserialize message for table redefinition", K(ret),
+      K(copy_indexes), K(copy_triggers), K(copy_constraints), K(copy_foreign_keys), K(ignore_errors), K(do_finish), K(*this));
   return ret;
 }
 
diff --git a/src/rootserver/ddl_task/ob_table_redefinition_task.h b/src/rootserver/ddl_task/ob_table_redefinition_task.h
index 43c24f6722..6f28b032e1 100644
--- a/src/rootserver/ddl_task/ob_table_redefinition_task.h
+++ b/src/rootserver/ddl_task/ob_table_redefinition_task.h
@@ -61,6 +61,10 @@ public:
   virtual void flt_set_task_span_tag() const override;
   virtual void flt_set_status_span_tag() const override;
   static bool check_task_status_before_pending(const share::ObDDLTaskStatus task_status);
+  INHERIT_TO_STRING_KV("ObDDLRedefinitionTask", ObDDLRedefinitionTask,
+      K(has_rebuild_index_), K(has_rebuild_constraint_), K(has_rebuild_foreign_key_),
+      K(is_copy_indexes_), K(is_copy_triggers_), K(is_copy_constraints_),
+      K(is_copy_foreign_keys_), K(is_ignore_errors_), K(is_do_finish_));
 protected:
   int table_redefinition(const share::ObDDLTaskStatus next_task_status);
   int copy_table_dependent_objects(const share::ObDDLTaskStatus next_task_status);
diff --git a/src/rootserver/ob_root_service.cpp b/src/rootserver/ob_root_service.cpp
index 2db8d77b9b..ecc535e8ea 100644
--- a/src/rootserver/ob_root_service.cpp
+++ b/src/rootserver/ob_root_service.cpp
@@ -3957,7 +3957,7 @@ int ObRootService::finish_redef_table(const obrpc::ObFinishRedefTableArg &arg)
 
 int ObRootService::copy_table_dependents(const obrpc::ObCopyTableDependentsArg &arg)
 {
-  LOG_DEBUG("receive copy table dependents arg", K(arg));
+  LOG_INFO("receive copy table dependents arg", K(arg));
   int ret = OB_SUCCESS;
   const int64_t task_id = arg.task_id_;
   const uint64_t tenant_id = arg.tenant_id_;