## Summary This issue is to roll out the feature introduced in https://gitlab.com/gitlab-org/gitlab/-/merge_requests/244213 on production, that is currently behind the `gitlab_duo_note_callback_high_urgency` feature flag. The flag gates the EventStore subscriptions for the new `Ai::Messaging::CallbackDispatchWorker` — the sole high-urgency EventStore subscriber that delivers DB-only `@GitLabDuo` note replies inline and forwards external-dependency adapters (e.g. Slack) to the pre-existing `Ai::Messaging::CallbackWorker`. Per [Sidekiq compatibility across updates](https://docs.gitlab.com/development/sidekiq/compatibility_across_updates/#adding-new-workers), a new worker's scheduling is gated behind a flag so jobs are not enqueued to the new queue before the Sidekiq fleet has rolled out the worker class. While the flag is off, `CallbackWorker` keeps delivering these adapters, so there is no delivery gap. **Feature flag definition:** - **Name:** `gitlab_duo_note_callback_high_urgency` - **Description:** Gate EventStore subscriptions for the new high-urgency Ai::Messaging::CallbackDispatchWorker so the new Sidekiq queue is only scheduled after the fleet has rolled out the worker class. - **Introduced by:** https://gitlab.com/gitlab-org/gitlab/-/merge_requests/244213 - **Milestone:** 19.2 - **Group:** group::ai coding - **Type:** gitlab_com_derisk - **Default enabled:** false ## Owners - Most appropriate Slack channel to reach out to: `#g_ai_coding` - Best individual to reach out to: @kinsingh ## Expectations ### What are we expecting to happen? When enabled, `@GitLabDuo` MR-mention note replies (the `gitlab_duo_note` adapter) are delivered by the new `:high`-urgency `CallbackDispatchWorker` instead of the low-urgency `CallbackWorker`, reducing the delay before Duo posts a reply. Slack delivery is unaffected — it always runs through `CallbackWorker` (external dependencies). While the flag is off, `CallbackWorker` continues to deliver the note replies (fallback), so behavior is preserved. ### What can go wrong and how would we detect it? - **High-urgency SLO breach:** the note path runs `Notes::CreateService`; if it exceeds the high-urgency SLO (median <1s, p99 <10s) it may pressure the shard. Monitor queue latency/duration for `ai_messaging_callback_dispatch`. - **Jobs enqueued before the fleet has the class:** mitigated by only enabling after the worker is deployed everywhere; if enabled too early, jobs sit in the new queue until Sidekiq catches up. - **Delivery regression:** if replies stop posting, disable the flag to fall back to `CallbackWorker`. Monitor: - Latency/error rates for `Ai::Messaging::CallbackDispatchWorker` and the `ai_messaging_callback_dispatch` queue on https://dashboards.gitlab.net - Exceptions in Sentry for the messaging adapters - User feedback in `#g_ai_coding` ## Rollout Steps Note: This is an instance-wide (`:instance`) flag, so it is enabled globally rather than per actor. 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 gitlab run auto_deploy status <merge-commit-of-your-feature>` - [ ] Enable the feature globally on non-production environments with `/chatops gitlab run feature set gitlab_duo_note_callback_high_urgency 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/). - See [`#e2e-run-staging` Slack channel](https://gitlab.enterprise.slack.com/archives/CBS3YKMGD) and look for the following messages: - test kicked off: `Feature flag gitlab_duo_note_callback_high_urgency has been set to true on **gstg**` - test result: `This pipeline was triggered due to toggling of gitlab_duo_note_callback_high_urgency feature flag` If you encounter end-to-end test failures and are unable to diagnose them, you may reach out to the [`#s_developer_experience` Slack channel](https://gitlab.enterprise.slack.com/archives/C07TWBRER7H) for assistance. Note that end-to-end test failures on `staging-ref` [don't block deployments](https://about.gitlab.com/handbook/engineering/infrastructure/environments/staging-ref/#how-to-use-staging-ref). ### Before production rollout - [ ] Confirm the new worker class has been deployed to the entire Sidekiq fleet on production before enabling the flag (this is the reason the subscription is gated). ### 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 gitlab run auto_deploy status <merge-commit-of-your-feature>` - [ ] Enable for a validation namespace first via the group actor: `/chatops gitlab run feature set --group=gitlab-org gitlab_duo_note_callback_high_urgency true` - [ ] Verify that `@GitLabDuo` note replies are delivered by the new worker for that namespace. ### 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. If a different developer will be covering, or an exception is needed, please inform the oncall SRE by using the `@sre-oncall` Slack alias. - [ ] Notify the [`#support_gitlab-com` Slack channel](https://gitlab.slack.com/archives/C4XFU81LG) and your team channel ([more guidance when this is necessary in the dev docs](https://docs.gitlab.com/development/feature_flags/controls/#communicate-the-change)). ### 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. - [ ] Enable the feature globally on production with `/chatops gitlab run feature set gitlab_duo_note_callback_high_urgency true`. - Monitor the appropriate graphs on https://dashboards.gitlab.net for at least 15 minutes afterward. - [ ] After the feature has been enabled, wait for [at least one day before releasing the feature](#release-the-feature). ### Release the feature After the feature has been [deemed stable](https://about.gitlab.com/handbook/product-development-flow/feature-flag-lifecycle/#including-a-feature-behind-feature-flag-in-the-final-release), 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. You can either [create a follow-up issue for Feature Flag Cleanup](https://gitlab.com/gitlab-org/gitlab/-/issues/new?issuable_template=Feature%20Flag%20Cleanup) or use the checklist below in this same issue. - [ ] Create a merge request to remove the `gitlab_duo_note_callback_high_urgency` feature flag. Ask for review/approval/merge as usual. The MR should include the following changes: - Make `CallbackDispatchWorker` the unconditional sole subscriber (remove the `if:` flag guards) and drop `CallbackWorker`'s EventStore subscriptions, keeping `CallbackWorker` only as the forward target for external-dependency adapters. - Remove all references to the feature flag from the codebase. - Remove the YAML definition for the feature from the repository. - [ ] Ensure that the cleanup MR has been included in the release package. If the merge request was deployed before [the monthly release was tagged](https://about.gitlab.com/handbook/engineering/releases/#self-managed-releases-1), the feature can be officially announced in a release blog post: `/chatops gitlab run release check <merge-request-url> <milestone>` - [ ] Once the cleanup MR has been deployed to production, clean up the feature flag from all environments by running these chatops command in `#production` channel: `/chatops gitlab run feature delete gitlab_duo_note_callback_high_urgency --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 gitlab run feature set gitlab_duo_note_callback_high_urgency false ``` - [ ] Disable the feature flag on non-production environments: ``` /chatops gitlab run feature set gitlab_duo_note_callback_high_urgency false --dev --pre --staging --staging-ref ``` - [ ] Delete feature flag from all environments: ``` /chatops gitlab run feature delete gitlab_duo_note_callback_high_urgency --dev --pre --staging --staging-ref --production ```