[IronPython] static source2handler mapping causing memory leaks
kamil at dworakowski.name
Tue Dec 18 10:32:01 CET 2007
I think I have found what is a design flaw in implementation of events
in IronPython that causes memory leaks. This seems to affect both IP 1.1
and IP 2.
As far as I understand the code of IP, there is an instance of
ReflectedEvent per event in a class (making it effectively static). This
ReflectedEvent object holds a hashtable from source of the event to a
handler. This hashtable is of class WeakHash in which keys are weak
references but the *values are strong references*.
There is a problem only for cases where GC can reach the source (the
key) by references starting from the handler (the value). This means
that values are keeping the keys alive and they will live happily ever
after just for themselves (and all their extended family, meaning the
objects that can be reach from them ;).
Why not make values of the mapping weak references too?
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