Hi, In what way is sqlalchemy dependend on pythons cyclic gc?, Is there any effort to make it work even if gc is off?.
I tried to turn gc off in a server side program i am developing, but this resulted in a lot of 'leaked' cycles/memory as soon as sqlalchemy is used to do some queries... I traced one cycle down to the relation between Session and SessionTransaction. They both hold a reference to each other, and this cycle is not broken in the session's close method, nor is one of them a weakref... Turning on gc leak detection, also showes a lot of IdentyManagedState objects being involved in cycles (e.g. not collected by refcount). The number of these objects just keeps growing with each query. Closing the Session has no influence on this... Depending on cyclic gc is detrimental to the performance of server side apps server serving many simultanious clients. The cyclic gc will halt the whole python process for up to seconds (if there is a large number of object instances in the process). All clients will thus experience quite some lag when the cycle gc kicks in. Unfortunatly with sqlalchemy tuning the gc to not run so often is also not good, because of the very large numbers of instances being created. A simple query for 2000 rows in my experience already creates about 10mb worth of sqlalchemy objects involved in cycles that need to be gc'd. So putting of the gc would mean memory would quickly be exhausted.... (i am using sqlalchemy trunk revision 5200) --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalchemy@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~----------~----~----~----~------~----~------~--~---
