CDRIVER-4227 Add a shared_mutex, and use it when locking in shared_ptr atomic operations #895
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
…ations Tag CDRIVER-4002
chardan
approved these changes
Nov 12, 2021
| */ | ||
| typedef struct bson_shared_mutex_t { | ||
| BSON_IF_WINDOWS (SRWLOCK native;) | ||
| BSON_IF_POSIX (pthread_rwlock_t native;) |
There was a problem hiding this comment.
to consider: Note that pthreads also has a pthread_mutex_t, which makes me wonder if bson_shared_mutex_t is the right name, especially as the platforms also make that distinction. bson_shared_rwlock? "Archibald"?
kevinAlbs
changed the title
kevinAlbs
reviewed
Nov 12, 2021
Co-authored-by: Kevin Albertson <[email protected]>
eramongodb
requested changes
Nov 12, 2021
This change only applies to private code, and does not expose any changes in the public API.
eramongodb
approved these changes
Nov 15, 2021
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Outdated suggestions cannot be applied.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.
At very high thread counts, locking on the shared_ptr atomic mutex begins to dominate. Using a shared_mutex significantly reduces the time spent in locking code and increases the performance under high contention. It could be improved further with a smarter use of the shared_ptr, but this is a significant basic improvement.