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A comment on Chris Lattner on garbage collection vs. Automatic Reference Counting (2017). Parent comment

Re:Chris Lattner on garbage collection vs. Automatic Referen... by hayley-patton on Sunday April 24, 2022 @08:39PM (#31149644)
I think a fair part of the unified theory is that a tracing GC traces live objects, whereas a refcounting GC traces dead objects.
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Re:Chris Lattner on garbage collection vs. Automatic Referen... by cmrdporcupine on Sunday April 24, 2022 @11:24PM (#31150473)
Upcounts trace live objects though. Just more incrementally.
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Re:Chris Lattner on garbage collection vs. Automatic Referen... by hayley-patton on Monday April 25, 2022 @02:15AM (#31151187)
By "trace" I mean the act of consulting the state of an object, then recursively tracing pointers in the object. A tracing GC propagates a "known to be live" state through an object graph while doing a collection cycle, and a refcounting GC propagates a "known to be dead" state through an object graph, when RC drops to zero.
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Re:Chris Lattner on garbage collection vs. Automatic Referen... by hmlongco on Tuesday April 26, 2022 @06:41PM (#31174069)
Umm... but isn't the refcounting GC more deterministic? If I create a chain of 10 object and then release the head, I run through 10 allocations and then 10 release cycles on those 10 objects. Period.
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