disk_striped: optimize futures vectors #2429
Open
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
In the `disk_striped` IO paths, use `Iterator::collect` instead of `push`ing into a `Vec`. Reimplement the chunk iterator to ensure it implements `TrustedLen`. This should ensure there's exactly one allocation for the futures array per IO and that the compiler constructs the futures directly into the array.
Contributor
There was a problem hiding this comment.
Pull Request Overview
This PR optimizes the performance of futures vector creation in disk_striped I/O functions by using Iterator::collect with iterators that implement TrustedLen, enabling single-allocation vector construction.
Key changes:
- Replaced custom
ChunkIterstruct with inlineRange::mapiterator forTrustedLenoptimization - Simplified error handling by replacing verbose
IoErrorenum with simplerLowerErrorstruct - Refactored futures creation from
forloops withVec::pushto iterator chains with.collect() - Improved test assertions using idiomatic
.expect()and.expect_err()methods
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
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Outdated suggestions cannot be applied.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.
Performance traces show that growing and populating the vector of futures in
disk_stripedIO functions is expensive. Optimize this: useIterator::collectto collect directly into theJoinAllthat we'll await, using an iterator that implementsTrustedLenso that the vector can allocate its buffer once and construct the futures in place.Also, clean up some impossible failure paths.