Flask-SQLAlchemy and Gevent not closing mysql connections -

i using flask-uwsgi-websockets provide websocket functionality application. use flask-sqlalchemy connect mysql database.

flask-uwsgi-websockets uses gevent manage websocket connections.

the problem having when websocket connection ended, database connection set flask-sqlalchemy keep on living.

i have tried calling db.session.close() , db.engine.dispose() after every websocket connection, had no effect.

calling gevent.monkey.patch_all() @ beginning of app not make difference.

a simple representation of doing this:

from gevent.monkey import patch_all patch_all()  flask import flask flask_uwsgi_websocket import geventwebsocket flask_sqlalchemy import sqlalchemy  app = flask() ws = geventwebsocket() db = sqlalchemy()  db.init_app(app) ws.init_app(app)   @ws.route('/ws') def websocket(client):     """ handle messages """     while client.connected true:         msg = client.recv()         # db stuff message      # following part executed when connection broken,     # tried removing connection, actual     # connection stay open (i can see on mysql server).     db.session.close()     db.engine.dispose() 

i have same situation. , solution me located in mysql configuration file my.cnf:

[mysqld] interactive_timeout=180 wait_timeout=180 

you must restart mysql service after save my.cnf.

if don't want restart mysql service can use sql queries:

set global interactive_timeout = 180; set global wait_timeout = 180; 

see wait_timeout , interactive_timeout on mysql.com