Leak investigation 2 #173
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Leak investigation 2 #173
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...which only shows up when you attach a debugger.
* Fix a memory leak in the inherited implementation.
* Write a new implementation:
* Written in my usual "obviously correct" style. (Bug notwithstanding, the
inherited version was basically correct, but it read to me more as "not
obviously wrong" than "obviously correct.")
* Uses `async` / `await` syntax where possible (which I generally prefer).
I'm going to leave the old implementation in for at least one PR before
removing it, for source history continuity.
…nto leak-investigation-2
This was referenced Mar 29, 2023
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This PR focuses on fixing the memory leaks that remained after addressing the ones fixed by introducing
Promise.race(), which were surprisingly non-zero in number.Promise.race()" implementation itself had a variation of the original leak, though it's super-understandable why it wasn't caught earlier. Specifically, the original version was tested by allocating bunches of objects which didn't have any references between them, so it was easy not to notice that there was (literally) one more than you'd expect when running the test to see if the new version leaked. In the case of this project, a single leak of the "wrong" race contender acts kind of like a trip-wire which then causes massive excess memory consumption (due to the nature of the links from eachLinkedEventto its next-event).LinkedEventwhich would then hold onto every subsequently-emitted event for the life of the process), it seemed worthwhile to work around the problem, which turned out not to be too awful to do. I left a big ole comment in the code explaining what's going on.