id,summary,reporter,owner,description,type,status,priority,milestone,component,resolution,keywords,cc,merged,author,reviewer,upstream,work_issues,branch,commit,dependencies,stopgaps
715,Parents probably not reclaimed due to too much caching,robertwb,somebody,"Here is a small example illustrating the issue.
The memory footprint of the following piece of code grows indefinitely.
{{{
sage: K = GF(1<<55,'t')
sage: a = K.random_element()
sage: while 1:
....: E = EllipticCurve(j=a); P = E.random_point(); 2*P; del E, P;
}}}
E and P get deleted, but when 2*P is computed, the action of integers on A, the abelian group of rational points of the ellitpic curve, gets cached in the corecion model.
A key-value pair is left in coercion_model._action_maps dict:
(ZZ,A,*) : IntegerMulAction
Moreover there is at least also references to A in the IntegerMulAction and one in ZZ._action_hash.
So weak refs should be used in all these places if it does not slow things too much.
'''To be merged with #11521'''. Apply:
* [attachment:715_all.patch]
and '''then''' the patches from #11521.",defect,positive_review,major,sage-5.5,coercion,,weak cache coercion Cernay2012,jpflori zimmerma vbraun robertwb nbruin malb,,"Simon King, Jean-Pierre Flori","Jean-Pierre Flori, Simon King, Nils Bruin",N/A,,,,"#13145, to be merged with #11521",