Refactor the task module #421
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
yoshuawuyts
changed the title
yoshuawuyts
changed the title
yoshuawuyts
reviewed
Nov 1, 2019
src/task/executor/pool.rs
Outdated
| // chosen point. | ||
| pool.stealers | ||
| .iter() | ||
| .chain(pool.stealers.iter()) |
There was a problem hiding this comment.
Heh, so how does this work? The chaining of pool.stealers with itself kind of confuses me.
There was a problem hiding this comment.
Yeah, it's a bit weird. :) I changed the code to:
// Try stealing a batch of tasks from each local queue starting from the
// chosen point.
let (l, r) = pool.stealers.split_at(start);
let rotated = r.iter().chain(l.iter());
rotated.map(|s| s.steal_batch_and_pop(&local)).collect()Hopefully now it's a bit clearer.
There was a problem hiding this comment.
Ah, I see now. Yeah that's better. Thank you!
ghost
merged commit
This pull request was closed.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Okay, this is a big PR. Sorry 😅
Nothing is fundamentally different from the previous implementation - I mostly reorganized the modules so that it becomes clearer what is where and what is what. While this doesn't really change our task executor, some small tweaks and the nature of cleaning things up made it a bit more efficient.
My primary motive here was to clearly separate what is the public API (what is visible in the generated docs for
async_std::task) and what is the task executor, i.e. the "machine" driving the module.The executor now lives in the
crate::task::drivermodule, and everything else is an implementation of the high-level API that really has nothing to do with the executor. For example,task_local!andblock_on()have meaty implementations, but are not a part of the executor itself and therefore that code does not live in thedrivermodule.There is also additional documentation and comments now, which should help contributors navigate the code more easily. In particular, I want people not interested in low-level details to not be lost in the codebase and people who are interested to be able to effortlessly play with the executor implementation without having to mess with anything that is unrelated to task execution.
This is the
taskmodule: https://github.com/stjepang/async-std/tree/refactor-task/src/taskThis is the
task::drivermodule: https://github.com/stjepang/async-std/tree/refactor-task/src/task/driverThe scheduler is less than 150 lines of code and this is its main part: https://github.com/stjepang/async-std/blob/refactor-task/src/task/driver/pool.rs