Downgrade the tx isolation level of poll message request flow #2614
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
It doesn't need a higher transaction isolation level as it's only loading a given poll message once, and we want to avoid putting any kind of locks on the PollMessage table as it seems to be having contention issues. Note that the poll message request flow is by far the most frequent code that touches the PollMessage table, as there are many many requests every minute from dozens of registrars, but much fewer poll messages than that to actually ACK.
|
This is a little bit of a shot in the dark, but do let me know what you think of it. |
|
I don't think this should matter given that this queries the replica instance, right? |
weiminyu
approved these changes
Nov 21, 2024
There was a problem hiding this comment.
Reviewed 1 of 1 files at r1, all commit messages.
Reviewable status:complete! all files reviewed, all discussions resolved (waiting on @gbrodman and @jianglai)
|
It will help provide some relief against contention on replica at least, but agreed that it probably doesn't target our main problem. |
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Outdated suggestions cannot be applied.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.
It doesn't need a higher transaction isolation level as it's only loading a given poll message once, and we want to avoid putting any kind of locks on the PollMessage table as it seems to be having contention issues. Note that the poll message request flow is by far the most frequent code that touches the PollMessage table, as there are many many requests every minute from dozens of registrars, but much fewer poll messages than that to actually ACK.
This change is