fix: disallow now_or_never (and async read)
#105
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BTW: I haven't been able to reproduce the panic though since the task budget accounting is somewhat nested and cannot be influenced via some direct API. |
tustvold
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Feb 16, 2022
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Tokio might preempt tasks at any point so `now_or_never` might return `None`. See https://tokio.rs/blog/2020-04-preemption We could try to workaround this by using data structures from `futures` instead of `tokio` which to not hook into the tokio cooperative scheduling. However this has certain drawbacks - The cooperative scheduling in tokio is actually not that bad, so we should rather work with it instead of against it. - The assumption that `futures` data structures don't participate in cooperative scheduling is only because currently they cannot interact with the runtime in any way. This might change when Rust's async ecosystem evolves so it kinda seems like a non-future-proof workaround. Fixes #102.
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Tokio might preempt tasks at any point so
now_or_nevermight returnNone. See https://tokio.rs/blog/2020-04-preemptionWe could try to workaround this by using data structures from
futuresinstead of
tokiowhich to not hook into the tokio cooperativescheduling. However this has certain drawbacks
should rather work with it instead of against it.
futuresdata structures don't participate incooperative scheduling is only because currently they cannot interact
with the runtime in any way. This might change when Rust's async
ecosystem evolves so it kinda seems like a non-future-proof
workaround.
Fixes #102.
While I'm on it I also disallowed async
readbecause it has the same issue as thewritecounterpart that we've already run into.