gh-112532: Isolate abandoned segments by interpreter #113717
Merged
Conversation
This file contains 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
Mimalloc segments are data structures that contain memory allocations along with metadata. Each segment is "owned" by a thread. When a thread exits, it abandons its segments to a global pool to be later reclaimed by other threads. This changes the pool to be per-interpreter instead of process-wide. This will be important for when we use mimalloc to find GC objects in the `--disable-gil` builds. We want heaps to only store Python objects from a single interpreter. Absent this change, the abandoning and reclaiming process could break this isolation.
DinoV
reviewed
Jan 4, 2024
There was a problem hiding this comment.
This probably doesn't matter for the actual Python usage because we use _mi_heap_init_ex, but do we need to initialize some value for tld_empty or set it in _mi_heap_init when we're off the main thread? I would think it just needs to be &_mi_abandoned_default to preserve the existing behavior.
|
@DinoV - yeah, that's right. I added the missing |
DinoV
approved these changes
Jan 4, 2024
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Outdated suggestions cannot be applied.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.
Mimalloc segments are data structures that contain memory allocations along with metadata. Each segment is "owned" by a thread. When a thread exits, it abandons its segments to a global pool to be later reclaimed by other threads. This changes the pool to be per-interpreter instead of process-wide.
This will be important for when we use mimalloc to find GC objects in the
--disable-gilbuilds. We want heaps to only store Python objects from a single interpreter. Absent this change, the abandoning and reclaiming process could break this isolation.--disable-gilbuilds #112532