diff --git a/src/observer/virtual_table/ob_virtual_show_trace.cpp b/src/observer/virtual_table/ob_virtual_show_trace.cpp
index 2e62eab53f..97b52b5677 100644
--- a/src/observer/virtual_table/ob_virtual_show_trace.cpp
+++ b/src/observer/virtual_table/ob_virtual_show_trace.cpp
@@ -112,7 +112,7 @@ int ObVirtualShowTrace::retrive_all_span_info()
       LOG_TRACE("send inner sql to retrive records", KP(session_), K(session_->get_proxy_sessid()),
                                                      K(session_->get_sessid()), K(table_name),
                                                      K(tenant_id_), K(trace_id_), K(trace_id),
-                                                     K(effective_tenant_id_));
+                                                     K(effective_tenant_id_), K(ObString(sql_len, sql)));
       if (sql_len >= OB_MAX_SQL_LENGTH || sql_len <= 0) {
         ret = OB_SIZE_OVERFLOW;
         SERVER_LOG(WARN, "failed to format sql. size not enough");
@@ -284,8 +284,9 @@ int ObVirtualShowTrace::generate_span_info_tree()
     if (OB_FAIL(ret)) {
       // do nothing
     } else if (!found_root) {
+      ret = OB_ERR_UNEXPECTED;
+      LOG_WARN("not found root span reset show trace", K(session_->get_last_flt_span_id()), K(session_->get_last_flt_trace_id()));
       show_trace_arr_.reset();
-      LOG_INFO("not found root span reset show trace");
     } else {
       // recursively generate span tree
       for (int64_t i = 0; OB_SUCC(ret) && i < root_arr.count(); ++i) {
diff --git a/src/sql/monitor/flt/ob_flt_utils.cpp b/src/sql/monitor/flt/ob_flt_utils.cpp
index 1db157fdb8..67996fe0a1 100644
--- a/src/sql/monitor/flt/ob_flt_utils.cpp
+++ b/src/sql/monitor/flt/ob_flt_utils.cpp
@@ -133,7 +133,6 @@ namespace sql
       session.set_auto_flush_trace(false);
       session.set_trace_enable(false);
     }
-    OZ(ObFLTUtils::init_flt_show_trace_env(session));
     return ret;
   }
 
@@ -412,7 +411,13 @@ namespace sql
         sid.deserialize(span_id.ptr(), span_id.length(), pos);
         OBTRACE->init(tid, sid);
         FLT_SET_TRACE_LEVEL(sess.get_control_info().level_);
+        if (sess.is_use_trace_log()) {
+          sess.set_auto_flush_trace(true);
+        }
         FLT_SET_AUTO_FLUSH(sess.is_auto_flush_trace());
+        char last_trace_id[OB_MAX_UUID_STR_LENGTH + 1];
+        pos = 0;
+        sid.tostring(last_trace_id, OB_MAX_UUID_STR_LENGTH + 1, pos);
       }
     // update trace_id by server self
     } else {
@@ -429,6 +434,9 @@ namespace sql
         }
       }
       FLT_SET_TRACE_LEVEL(sess.get_control_info().level_);
+      if (sess.is_use_trace_log()) {
+        sess.set_auto_flush_trace(true);
+      }
       FLT_SET_AUTO_FLUSH(sess.is_auto_flush_trace());
     }
 
@@ -567,14 +575,22 @@ namespace sql
       // record span
       if (OB_FAIL(ret)) {
         // do nothing
-      } else if (OB_FAIL(flt_span_manager->record_span(data))) {
-        if (OB_SIZE_OVERFLOW == ret || OB_ALLOCATE_MEMORY_FAILED == ret) {
-          LOG_TRACE("cannot allocate mem for record", K(ret));
-          ret = OB_SUCCESS;
-        } else {
-          if (REACH_TIME_INTERVAL(100 * 1000)) { // in case logging is too frequent
-            LOG_WARN("failed to record request info in request manager", K(ret));
+      } else {
+        while (true) {
+          if (OB_FAIL(flt_span_manager->record_span(data))) {
+            if (OB_SIZE_OVERFLOW == ret || OB_ALLOCATE_MEMORY_FAILED == ret) {
+              LOG_TRACE("cannot allocate mem for record", K(ret));
+              ret = OB_SUCCESS;
+            } else {
+              if (REACH_TIME_INTERVAL(100 * 1000)) { // in case logging is too frequent
+                LOG_WARN("failed to record request info in request manager", K(ret));
+              }
+            }
           }
+          // If the slot is full, a certain amount of
+          // internal space will be released,
+          // and it needs to be added again
+          if (ret != OB_ENTRY_NOT_EXIST) break;
         }
       }
     }
diff --git a/src/sql/resolver/cmd/ob_show_resolver.cpp b/src/sql/resolver/cmd/ob_show_resolver.cpp
index 21fac49bbe..6d3a0c70d4 100644
--- a/src/sql/resolver/cmd/ob_show_resolver.cpp
+++ b/src/sql/resolver/cmd/ob_show_resolver.cpp
@@ -709,6 +709,9 @@ int ObShowResolver::resolve(const ParseNode &parse_tree)
           if (OB_UNLIKELY(parse_tree.num_child_ != 2 || NULL == parse_tree.children_)) {
             ret = OB_ERR_UNEXPECTED;
             LOG_WARN("parse tree is wrong", K(ret), K(parse_tree.num_child_), K(parse_tree.children_));
+          } else if (!session_info_->get_control_info().is_valid()) {
+            ret = OB_NOT_SUPPORTED;
+            LOG_USER_ERROR(OB_NOT_SUPPORTED, "If full link tracing is not enabled, show trace is");
           } else {
             show_resv_ctx.condition_node_ = parse_tree.children_[0];
             show_resv_ctx.stmt_type_ = stmt::T_SHOW_TRACE;