avoid brief cache too often

mindinsight/datavisual/data_transform/data_manager.py

@@ -862,11 +862,10 @@ class DataManager:
         """
         logger.info("Start to load data")
         DataManager.check_reload_interval(reload_interval)
-        thread = threading.Thread(target=self._load_data_in_thread_wrapper,
+        thread = threading.Thread(target=self._load_data_in_thread,
                                   name='start_load_data_thread',
                                   args=(reload_interval,),
                                   daemon=True)
-        thread.daemon = True
         thread.start()
         return thread
 
@@ -884,7 +883,7 @@ class DataManager:
         if reload_interval < 0:
             raise ParamValueError("The value of reload interval should be >= 0.")
 
-    def _load_data_in_thread_wrapper(self, reload_interval):
+    def _load_data_in_thread(self, reload_interval):
         """Wrapper for load data in thread."""
         if self._load_data_lock.locked():
             return
@@ -911,8 +910,13 @@ class DataManager:
                                       max_processes_cnt=settings.MAX_PROCESSES_COUNT) as computing_resource_mgr:
             with computing_resource_mgr.get_executor() as executor:
                 self._brief_cache.update_cache(executor)
+                brief_cache_update = time.time()
                 for _ in self._detail_cache.update_cache(executor):
-                    self._brief_cache.update_cache(executor)
+                    update_interval = time.time() - brief_cache_update
+                    logger.debug('Loading one round of detail cache taking %ss.', update_interval)
+                    if update_interval > 3: # Use 3 seconds as threshold to avoid updating too often
+                        self._brief_cache.update_cache(executor)
+                        brief_cache_update += update_interval
                 executor.wait_all_tasks_finish()
             with self._status_mutex:
                 if not self._brief_cache.has_content() and not self._detail_cache.has_content():