Lower the async task slab allocation to 1000 bytes. #38727
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
Due to malloc quanta rounding, 1024-byte async task allocation slabs actually end up allocating 1536 bytes on Darwin. Instead, use 1000-byte slabs. Fixes rdar://81181856.
|
@swift-ci please smoke test and merge |
mikeash
approved these changes
Aug 2, 2021
ktoso
approved these changes
Aug 2, 2021
rjmccall
reviewed
Aug 3, 2021
| /// | ||
| /// TODO: find the optimal value by experiment. | ||
| static constexpr size_t SlabCapacity = 1024; | ||
| static constexpr size_t SlabCapacity = 1000; |
There was a problem hiding this comment.
The way we make this a template argument is unfortunate, because it means we have to write it out here where we can't adjust it for the slab header size, which is what we obviously should be doing instead of this magic-number adjustment.
It should probably also be smaller on 32-bit platforms.
There was a problem hiding this comment.
Maybe we could change the semantics of the template argument so that it's the requested malloc size instead of the requested slab size.
There was a problem hiding this comment.
Yeah. Let's separate out a task to make this more robust in the future.
|
@swift-ci please smoke test Linux |
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Outdated suggestions cannot be applied.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.
Due to malloc quanta rounding, 1024-byte async task allocation slabs
actually end up allocating 1536 bytes on Darwin. Instead, use 1000-byte
slabs.
Fixes rdar://81181856.