Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

kvdb/postgres: remove global application level lock #8644

Merged

Conversation

Roasbeef
Copy link
Member

In this commit, we remove the global application level lock from the postgres backend. This lock prevents multiple write transactions from happening at the same time, and will also block a writer if a read is on going. Since this lock was added, we know always open DB connections with the strongest level of concurrency control available: LevelSerializable. In concert with the new auto retry logic, we ensure that if db transactions conflict (writing the same key/row in this case), then the tx is retried automatically.

Removing this lock should increase perf for the postgres backend, as now concurrent write transactions can proceed, being serialized as needed. Rather then trying to handle concurrency at the application level, we'll set postgres do its job, with the application only needing to retry as necessary.

Remake of #7992

@Roasbeef Roasbeef added database Related to the database/storage of LND optimization concurrency labels Apr 12, 2024
Copy link
Contributor

coderabbitai bot commented Apr 12, 2024

Important

Review skipped

Auto reviews are limited to specific labels.

🏷️ Labels to auto review (1)
  • llm-review

Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.


Thank you for using CodeRabbit. We offer it for free to the OSS community and would appreciate your support in helping us grow. If you find it useful, would you consider giving us a shout-out on your favorite social media?

❤️ Share
🪧 Tips

Chat

There are 3 ways to chat with CodeRabbit:

  • Review comments: Directly reply to a review comment made by CodeRabbit. Example:
    • I pushed a fix in commit <commit_id>, please review it.
    • Generate unit testing code for this file.
    • Open a follow-up GitHub issue for this discussion.
  • Files and specific lines of code (under the "Files changed" tab): Tag @coderabbitai in a new review comment at the desired location with your query. Examples:
    • @coderabbitai generate unit testing code for this file.
    • @coderabbitai modularize this function.
  • PR comments: Tag @coderabbitai in a new PR comment to ask questions about the PR branch. For the best results, please provide a very specific query, as very limited context is provided in this mode. Examples:
    • @coderabbitai gather interesting stats about this repository and render them as a table. Additionally, render a pie chart showing the language distribution in the codebase.
    • @coderabbitai read src/utils.ts and generate unit testing code.
    • @coderabbitai read the files in the src/scheduler package and generate a class diagram using mermaid and a README in the markdown format.
    • @coderabbitai help me debug CodeRabbit configuration file.

Note: Be mindful of the bot's finite context window. It's strongly recommended to break down tasks such as reading entire modules into smaller chunks. For a focused discussion, use review comments to chat about specific files and their changes, instead of using the PR comments.

CodeRabbit Commands (Invoked using PR comments)

  • @coderabbitai pause to pause the reviews on a PR.
  • @coderabbitai resume to resume the paused reviews.
  • @coderabbitai review to trigger an incremental review. This is useful when automatic reviews are disabled for the repository.
  • @coderabbitai full review to do a full review from scratch and review all the files again.
  • @coderabbitai summary to regenerate the summary of the PR.
  • @coderabbitai resolve resolve all the CodeRabbit review comments.
  • @coderabbitai configuration to show the current CodeRabbit configuration for the repository.
  • @coderabbitai help to get help.

Other keywords and placeholders

  • Add @coderabbitai ignore anywhere in the PR description to prevent this PR from being reviewed.
  • Add @coderabbitai summary to generate the high-level summary at a specific location in the PR description.
  • Add @coderabbitai anywhere in the PR title to generate the title automatically.

CodeRabbit Configuration File (.coderabbit.yaml)

  • You can programmatically configure CodeRabbit by adding a .coderabbit.yaml file to the root of your repository.
  • Please see the configuration documentation for more information.
  • If your editor has YAML language server enabled, you can add the path at the top of this file to enable auto-completion and validation: # yaml-language-server: $schema=https://coderabbit.ai/integrations/schema.v2.json

Documentation and Community

  • Visit our Documentation for detailed information on how to use CodeRabbit.
  • Join our Discord Community to get help, request features, and share feedback.
  • Follow us on X/Twitter for updates and announcements.

@saubyk saubyk requested review from a team, bhandras and yyforyongyu and removed request for a team April 14, 2024 17:51
@lightninglabs-deploy
Copy link

@bhandras: review reminder
@yyforyongyu: review reminder

@Roasbeef
Copy link
Member Author

Gonna close then re-open so CI can run again.

@Roasbeef Roasbeef closed this Aug 20, 2024
@Roasbeef Roasbeef reopened this Aug 20, 2024
@aakselrod
Copy link
Contributor

would be nice to see this rebased since the nativesql tests run correctly now as well

@Roasbeef
Copy link
Member Author

Rebased!

Copy link
Collaborator

@ellemouton ellemouton left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

nice - LGTM

(am assuming the native sql postgres itest error is unrelated to this)

Copy link
Member

@yyforyongyu yyforyongyu left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

LGTM🦾 - confirm the itest failures are flakes.

@aakselrod
Copy link
Contributor

LGTM too!

@Roasbeef
Copy link
Member Author

Rebasing. I don't think the failures are flakes (last I looked at the logs, wallet related tests we're failing), we'll see with the next CI run.

In this commit, we remove the global application level lock from the
postgres backend. This lock prevents multiple write transactions from
happening at the same time, and will also block a writer if a read is on
going. Since this lock was added, we know always open DB connections
with the strongest level of concurrency control available:
`LevelSerializable`. In concert with the new auto retry logic, we ensure
that if db transactions conflict (writing the same key/row in this
case), then the tx is retried automatically.

Removing this lock should increase perf for the postgres backend, as now
concurrent write transactions can proceed, being serialized as needed.
Rather then trying to handle concurrency at the application level, we'll
set postgres do its job, with the application only needing to retry as
necessary.
@Roasbeef
Copy link
Member Author

Roasbeef commented Oct 1, 2024

Kicked CI to re-run....yuge W here if this passes!

@Roasbeef
Copy link
Member Author

Roasbeef commented Oct 2, 2024

aaaand we're ✅

@Roasbeef Roasbeef merged commit 9f0cc15 into lightningnetwork:master Oct 2, 2024
29 of 34 checks passed
@guggero
Copy link
Collaborator

guggero commented Oct 28, 2024

aaaand we're ✅

Unfortunately because of the missing replace directives in go.mod... I guess we need a CI step that adds a warning comment to a PR if the code it changes doesn't actually run in the CI.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
concurrency database Related to the database/storage of LND optimization
Projects
None yet
Development

Successfully merging this pull request may close these issues.

6 participants