0.5 second connection overhead

I’m having some issues with my connection requests ever since I have followed the best practices defined in the docs:

Code in docs:

from flask import Flask
from peewee import *

database = SqliteDatabase('my_app.db')
app = Flask(__name__)

# This hook ensures that a connection is opened to handle any queries
# generated by the request.
@app.before_request
def _db_connect():
    database.connect()

# This hook ensures that the connection is closed when we've finished
# processing the request.
@app.teardown_request
def _db_close(exc):
    if not database.is_closed():
        database.close()

After this change, all handled requests have a 0.5 second overhead in response time.

I’m currently investigating and was wondering if this was something that could be somehow caused by Peewee’s handling/closing of new connections, or if it is something else.

Thanks for your help.

Will

[NicolasCaous]

Your snippet is opening and closing a database connection at every request. There is an overhead time built into it (You can’t escape it). Maybe you should consider altering the way in which you manage connections. Something like:

Open a connection at startup.

On @app.before_request verify that the connection wasn’t closed by the database (or by any other reason). If it’s closed, open it again, otherwise, recycle the connection.

You may be interested in a pooled connection.

Edit

This is a bad advice, see @coleifer comment for clarification.

[NicolasCaous]

Yes, you can use a connection string to configure the pooled database connection.

http://docs.peewee-orm.com/en/latest/peewee/playhouse.html#connect

The kwargs are parsed from the URL query parameters.