src: do not track weak BaseObjects as childrens of Realms#63842
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addaleax wants to merge 4 commits into
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src: do not track weak BaseObjects as childrens of Realms#63842addaleax wants to merge 4 commits into
BaseObjects as childrens of Realms#63842addaleax wants to merge 4 commits into
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Allowing the addition of child nodes without an explicit edge between them enables expressing a relationship of the "node A keeps track of node B and no other node does, but node A does not keep node B alive" kind, which is the relationship between `Realm`s and weak `BaseObject` instances. This is a prerequisite for the following commit. Signed-off-by: Anna Henningsen <anna@addaleax.net>
Heap dumps are used for analyzing the relationship between objects that keep each other alive, so that retainers of memory can be detected and memory leaks fixed. 6e60ab7 broke this for a wide range of `BaseObject` instances. Marking all `BaseObject`s, including weak ones, as children of `Realm` and `Environment` instances gives the incorrect impression that they are held alive by those objects, effectively hiding the "real" set of strong roots that keep other objects alive through GC. While I still disagree with the decision in 6e60ab7 not to mark strong `BaseObject`s as proper roots in the object graph, this commit keeps that decision intact, and only removes edges to weak `BaseObject` instances. Refs: nodejs#57417 Signed-off-by: Anna Henningsen <anna@addaleax.net>
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src: allow tracking children in
MemoryTrackerwithout edgesAllowing the addition of child nodes without an explicit edge
between them enables expressing a relationship of the
"node A keeps track of node B and no other node does,
but node A does not keep node B alive" kind, which is
the relationship between
Realms and weakBaseObjectinstances.This is a prerequisite for the following commit.
src: do not track weak
BaseObjects as childrens ofRealmsHeap dumps are used for analyzing the relationship between
objects that keep each other alive, so that retainers of
memory can be detected and memory leaks fixed.
6e60ab7 broke this for a wide range of
BaseObjectinstances. Marking all
BaseObjects, including weak ones,as children of
RealmandEnvironmentinstances givesthe incorrect impression that they are held alive by those
objects, effectively hiding the "real" set of strong roots
that keep other objects alive through GC.
While I still disagree with the decision in 6e60ab7
not to mark strong
BaseObjects as proper roots in theobject graph, this commit keeps that decision intact, and only
removes edges to weak
BaseObjectinstances.Refs: #57417