Python-pyramid application memory not released at all

Question

Python-pyramid application memory not released at all

How to solve this memory leak?

What measures should be taken to clean up old session objects? Is session.close() enough?

or

Is this something related to the pyramid?

 Sqlalchmey setup: ---------------------------------------------------------------------------------- def get_db(request): maker = request.registry.dbmaker session = maker() @profile def cleanup(request): _session = request.db if request.exception is not None: _session.rollback() else: _session.commit() _session.close() # del _session # No memory released request.add_finished_callback(cleanup) return session def main(global_config, **settings): : : config.registry.dbmaker = sessionmaker(bind=engine) config.add_request_method(get_db, name='db', reify=True) : :

Pyramid's application request handler is similar to

 @view_config(route_name='list_employees', renderer='json') def employees(request): session = request.db office = session.query(Office).get(1) employees = [x.name for x in office.employees] return employees

Now the problem is that in every list_employees request, memory is growing. the size of the increase in memory is almost equal to the size of office.employees.

Debug:

 request 1 starts with memory utilization = 10MB request 1 ends with memory utilization = 18MB request 2 starts with memory utilization = 18MB request 2 ends with memory utilization = 26MB request 3 starts with memory utilization = 26MB request 3 ends with memory utilization = 34MB : : Grows eventually employees = [x.name for x in office.employees] This is the line where about 8-10MB memory utilized

To debug, I added the __ del __ method in the Employ and Office models, it looks like they are being deleted.

Also tried session.expunge(office) , del office and gc.collect()

I am debugging memory consumption using https://pypi.python.org/pypi/memory_profiler Also I use https://pypi.python.org/pypi/transaction other requests.

Do not use the toolbar to debug the pyramid.

EDIT : An increase in memory was detected on this line (employees = [x.name for x in office.employees]) shows zero after 6-7 queries. But the query returned the same number of rows.

EDIT : Added standalone app https://github.com/Narengowda/pyramid_sqlalchemy_app

EDIT : ITS NOT RELATED TO SQLALCHEMY FOR EVERYONE (my bad). Wrote a simple view function that has no sqlalchmey queries.

 class Test(object): def __init__(self): self.x = 'sdfklhasdjkfhasklsdkjflksdfksd' *1000 self.y = 'sdfklhasdjkfhasklsdkjflksdfksd' *1000 self.z = 'sdfklhasdjkfhasklsdkjflksdfksd' *1000 self.i = 'sdfklhasdjkfhasklsdkjflksdfksd' *1000 self.v = 'sdfklhasdjkfhasklsdkjflksdfksd' *1000 self.o = 'sdfklhasdjkfhasklsdkjflksdfksd' *1000 @view_config(route_name='home', renderer='json') def my_view(request): return test(request) @profile def test(request): count = request.GET.get('count') l = [Test() for i in range(int(count))] print l[0] return {}

I can see it below, magazines magazines