[ZScheduler] Store pointers to mutable references in stack memory to avoid reading them from the heap #9868
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…avoid fetching them from the heap
hearnadam
approved these changes
May 17, 2025
| if (currentBlocking) { | ||
| val runnables = localQueue.pollUpTo(256) | ||
| if (runnables.nonEmpty) { | ||
| if (!runnables.isEmpty) { |
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Is this because of the interface dispatch? I think we could override it even though it's marked deprecatedOverriding
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Is this because of the interface dispatch
Yeap
I think we could override it
I'm a bit worried that it'll make things a bit worse for the rest of the std library collections. My knowledge on the matter is not the best but I think that the more overrides a method has, it makes interface dispatches for that method slower. I could be wrong on that though, I vaguely remember reading that somewhere.
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With this PR we store references to mutable objects in vals within the
ZWorker#runmethod. This way we avoid reading them from the heap, reducing the potential of their value being invalidated in case they fall in a cache line that contains a variable that is regularly updated