## Summary This issue is to roll out [the async pipeline creation for new merge requests](https://gitlab.com/groups/gitlab-org/-/epics/10991) on production, that is currently behind the `async_mr_pipeline_creation` feature flag. **Related MR:** https://gitlab.com/gitlab-org/gitlab/-/merge_requests/217381 ## Owners - Most appropriate Slack channel to reach out to: `#g_code_review` - Best individual to reach out to: @marc_shaw ## Expectations ### What are we expecting to happen? When enabled, pipeline creation for new merge requests will be performed asynchronously via `MergeRequests::CreatePipelineWorker` instead of synchronously in `NewMergeRequestWorker`. This should reduce the P90 latency of `NewMergeRequestWorker` from over 3 seconds to under 1 second (S3 criteria target). ### What can go wrong and how would we detect it? - Pipeline creation could fail silently or be delayed, causing merge requests to appear without pipelines longer than expected - Monitor `NewMergeRequestWorker` latency metrics and pipeline creation success rates - Watch for increased errors in `MergeRequests::CreatePipelineWorker` - Check for user reports of missing pipelines on newly created merge requests ## Rollout Steps Note: Please make sure to run the chatops commands in the Slack channel that gets impacted by the command. ### Rollout on non-production environments - Verify the MR with the feature flag is merged to `master` and has been deployed to non-production environments with `/chatops run auto_deploy status <merge-commit-of-your-feature>` - [ ] Deploy the feature flag at a percentage (recommended percentage: 50%) with `/chatops run feature set async_mr_pipeline_creation 50 --actors --dev --pre --staging --staging-ref` - [ ] Monitor that the error rates did not increase (repeat with a different percentage as necessary). - [ ] Enable the feature globally on non-production environments with `/chatops run feature set async_mr_pipeline_creation true --dev --pre --staging --staging-ref` - [ ] Verify that the feature works as expected. The best environment to validate the feature in is [`staging-canary`](https://about.gitlab.com/handbook/engineering/infrastructure/environments/#staging-canary) as this is the first environment deployed to. Make sure you are [configured to use canary](https://next.gitlab.com/). - [ ] If the feature flag causes end-to-end tests to fail, disable the feature flag on staging to avoid blocking [deployments](https://about.gitlab.com/handbook/engineering/deployments-and-releases/deployments/). ### Before production rollout - [ ] If the change is significant and you wanted to announce in [#whats-happening-at-gitlab](https://gitlab.enterprise.slack.com/archives/C0259241C), it best to do it before rollout to `gitlab-org/gitlab-com`. ### Specific rollout on production For visibility, all `/chatops` commands that target production must be executed in the [`#production` Slack channel](https://gitlab.slack.com/archives/C101F3796) and cross-posted (with the command results) to the responsible team's Slack channel. - Ensure that the feature MRs have been deployed to both production and canary with `/chatops run auto_deploy status <merge-commit-of-your-feature>` - [ ] For **project-actor**: `/chatops run feature set --project=gitlab-org/gitlab,gitlab-org/gitlab-foss,gitlab-com/www-gitlab-com async_mr_pipeline_creation true` - [ ] Verify that the feature works for the specific actors. ### Preparation before global rollout - [ ] Set a milestone to this rollout issue to signal for enabling and removing the feature flag when it is stable. - [ ] Check if the feature flag change needs to be accompanied with a [change management issue](https://about.gitlab.com/handbook/engineering/infrastructure-platforms/change-management/#feature-flags-and-the-change-management-process). Cross link the issue here if it does. - [ ] Ensure that you or a representative in development can be available for at least 2 hours after feature flag updates in production. - [ ] Ensure that documentation exists for the feature, and the [version history text](https://docs.gitlab.com/development/documentation/feature_flags/#add-history-text) has been updated. - [ ] Notify the [`#support_gitlab-com` Slack channel](https://gitlab.slack.com/archives/C4XFU81LG) and your team channel. ### Global rollout on production For visibility, all `/chatops` commands that target production must be executed in the [`#production` Slack channel](https://gitlab.slack.com/archives/C101F3796) and cross-posted (with the command results) to the responsible team's Slack channel. - [ ] [Incrementally roll out](https://docs.gitlab.com/development/feature_flags/controls/#process) the feature on production. - `/chatops run feature set async_mr_pipeline_creation 10 --actors` - `/chatops run feature set async_mr_pipeline_creation 25 --actors` - `/chatops run feature set async_mr_pipeline_creation 50 --actors` - `/chatops run feature set async_mr_pipeline_creation 100 --actors` - Between every step wait for at least 15 minutes and monitor the appropriate graphs on https://dashboards.gitlab.net. - [ ] After the feature has been 100% enabled, wait for at least one day before releasing the feature. ### Release the feature After the feature has been deemed stable, the [clean up](https://docs.gitlab.com/development/feature_flags/controls/#cleaning-up) should be done as soon as possible to permanently enable the feature and reduce complexity in the codebase. - [ ] Create a merge request to remove the `async_mr_pipeline_creation` feature flag. The MR should include: - Remove all references to the feature flag from the codebase. - Remove the YAML definitions for the feature from the repository. - [ ] Ensure that the cleanup MR has been included in the release package. - [ ] Once the cleanup MR has been deployed to production, clean up the feature flag from all environments: `/chatops run feature delete async_mr_pipeline_creation --dev --pre --staging --staging-ref --production` - [ ] Close this rollout issue. ## Rollback Steps - [ ] This feature can be disabled on production by running the following Chatops command: ``` /chatops run feature set async_mr_pipeline_creation false ``` - [ ] Disable the feature flag on non-production environments: ``` /chatops run feature set async_mr_pipeline_creation false --dev --pre --staging --staging-ref ``` - [ ] Delete feature flag from all environments: ``` /chatops run feature delete async_mr_pipeline_creation --dev --pre --staging --staging-ref --production ```