diff --git a/server/visualdl/visual_dl.py b/server/visualdl/visual_dl.py
index b28a496dc8a4b94dce90378bc5a1de0a281d83c1..f34fd8b0dbf3bbd26d26063b66e37f756b205756 100644
--- a/server/visualdl/visual_dl.py
+++ b/server/visualdl/visual_dl.py
@@ -16,11 +16,12 @@ import storage
 import graph
 
 app = Flask(__name__, static_url_path="")
+# set static expires in a short time to reduce browser's memory usage.
+app.config['SEND_FILE_MAX_AGE_DEFAULT'] = 30
 
 
 def option_parser():
     """
-
     :return:
     """
     parser = OptionParser(usage="usage: visual_dl visual_dl.py "\
@@ -152,6 +153,7 @@ def individual_image():
         imagefile, as_attachment=True, attachment_filename='img.png')
     return response
 
+
 @app.route('/data/plugin/graphs/graph')
 def graph():
     model_json = graph.load_model("")