On Sep 25, 2014, at 4:33 AM, Thierry Florac <tflo...@gmail.com> wrote:
> Hi, > > I have a multi-threaded web application using SQLAlchemy connections pool. > As soon as a connection is opened, it's maintained opened in the pool even if > it's not used anymore. On a long run, this can consume too much unnecessary > connections and database server resources. > > So what I'm actually looking for is a way to close a given connection which > is returned to the pool if it wasn't used for a given amount of time... OK well first we assume that you do want pooling in the first place. If you just don't want any, you'd use NullPool. So assuming you do want pooling, the next thing that resembles what you describe, but I'm guessing still is not what you want, is the pool_recycle setting, which will prevent a connection that is older than N seconds from being used. This recycle occurs when the connection is to be fetched; if it is past the expiration time, it is closed and replaced with a new one. However the connection stays in the pool until the pool is accessed. So the final option is, you want the connection returned to the pool while the pool is idle. The challenge there is that nothing is happening in the app to make this happen, which implies a background thread or other asynchronous task system, so you'd have to roll that yourself. Overall if you have more detailed pooling needs the suggestion to use PGBouncer is probably a good one. If it were me, I'd just use a low pool size, just have 5 connections hanging around with a higher overflow. -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
