Remove the shared state and the mutex from NVTX internals - #2310
Merged
rapids-bot[bot] merged 2 commits intoMay 15, 2024
Conversation
achirkin
added
3 - Ready for Review
improvement
tfeher
requested changes
May 14, 2024
tfeher
left a comment
tfeher
left a comment
Contributor
There was a problem hiding this comment.
Thanks Artem for the PR, looks good, just a small update in docstring is missing!
tfeher
approved these changes
May 14, 2024
tfeher
left a comment
tfeher
left a comment
Contributor
There was a problem hiding this comment.
Thanks for the update, LGTM!
cjnolet
approved these changes
May 14, 2024
Contributor
Author
|
/merge |
loulankxh
pushed a commit
to loulankxh/raft
that referenced
this pull request
Oct 14, 2025
Until now, raft has stored a map of NVTX colors (annotation -> color) to avoid using the same color for different annotations and keep using the same color for the same annotations. This map is a shared state. During an extensive ANN_BENCH throughput testing it has turned out that the mutex guarding the map can sometimes become a bottleneck when the number of concurrent threads is really large (>~ 256). This PR replaces the unordered map and the mutex guarding it with a deterministic hash value of the annotation instead (which is stateless). **Pros:** - No shared state, no mutexes. - Assigns the same colors to the same annotations across program runs. **Cons:** - Sometimes different annotations can have the same color (hash collisions). Authors: - Artem M. Chirkin (https://github.com/achirkin) Approvers: - Tamas Bela Feher (https://github.com/tfeher) - Corey J. Nolet (https://github.com/cjnolet) URL: NVIDIA#2310
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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
4 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.
Until now, raft has stored a map of NVTX colors (annotation -> color) to avoid using the same color for different annotations and keep using the same color for the same annotations. This map is a shared state.
During an extensive ANN_BENCH throughput testing it has turned out that the mutex guarding the map can sometimes become a bottleneck when the number of concurrent threads is really large (>~ 256). This PR replaces the unordered map and the mutex guarding it with a deterministic hash value of the annotation instead (which is stateless).
Pros:
Cons: