add docs on task migration #50047
add docs on task migration #50047
Conversation
IanButterworth
added
docs
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Would it be a good idea to suggest an alternative to indexing using |
Yeah. There's a bit of a concerted effort going on currently to help clarify behavior and guidance on that. One part is #48542. Another is a guide post that's being drafted. |
| [`@threads`](@ref Threads.@threads)), it may move to a different thread if the task yields. | ||
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| This means that [`threadid()`](@ref Threads.threadid) should not be treated as constant within a task, and therefore | ||
| should not be used to index into a vector of buffers or stateful objects. |
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Shall we say "Instead, prefer making judicious use of task_local_storage(), or pass values around as explicit arguments."
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I think what we should advise is that people use @spawn because @spawned tasks can define and return values.
That's a lot nicer as an API than having users trying to reason about shared buffers, or them trying to reach into and keep track of task_local_storage()s
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We could keep this PR as is then figure out the recommended patterns in #48542?
(cherry picked from commit ff23b37)
(cherry picked from commit ff23b37)
(cherry picked from commit ff23b37)
#40715 introduced task migration (in 1.7)
#43496 removed pre-1.7 docs that said task migration didn't happen
It seems important-enough and surprising-enough to explicitly document.