+ # This pool size is per configured database. The minimum needed,
+ # determined by binary search, is 23. We're using 25 so we have a bit
+ # more playroom, and then the overflow should make sure things don't
+ # break when we suddenly need more.
+ pool_args = {'poolclass': QueuePool,
+ 'pool_size': 25,
+ 'max_overflow': 50}
+ if engine_name.startswith('sqlite://'):
+ # It's not possible to share connections for SQLite between
+ # threads, so let's use the SingletonThreadPool for them
+ pool_args = {'poolclass': SingletonThreadPool}
+ # pylint: disable=star-args
+ self._dbengine = create_engine(engine_name, **pool_args)