runtime: move owned field to Trailer #4843
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Darksonn
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A-tokio
hawkw
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Jul 19, 2022
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This PR moves the
ownedfield from the task header to the trailer.Motivation. Various other PRs have run into trouble with the header not having enough space to add new fields. This PR exists to make more space in the header for those other PRs.
Why is this ok? The purpose of the trailer is to store fields only needed during shutdown of the task, and the
ownedfield is only accessed during shutdown (and creation) of tasks, and during shutdown of the runtime. Thus, it is only rarely accessed. This makes it ok to store the field in cold memory.