[GPRD] Configuring Gitlab Rails for sidekiq sharding
Production Change
Change Summary
The change configures Gitlab.com to be ready for a sharded Sidekiq setup. See scalability#3173 (closed) for overview on the plan.
This CR focuses on configuring k8s and chef nodes with the updated routing rules and new Redis configuration details.
Change Details
- Services Impacted - ServiceSidekiq ServiceRedisSidekiq
- Change Technician - @schin1
- Change Reviewer - @fshabir
- Time tracking - 1.5 h
- Downtime Component - NA
Set Maintenance Mode in GitLab
If your change involves scheduled maintenance, add a step to set and unset maintenance mode per our runbooks. This will make sure SLA calculations adjust for the maintenance period.
Detailed steps for the change
Change Steps - steps to take to execute the change
Estimated Time to Complete (90 mins)
-
Set label changein-progress /label ~change::in-progress
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Add secrets for rails user into vault -- see https://gitlab.com/gitlab-com/runbooks/-/blob/master/docs/redis/provisioning-redis-cluster.md#3-configure-gitlab-rails for details -
Merge chef MR to configure deployer and console nodes. Note that password needs to be set now - redis config: https://gitlab.com/gitlab-com/gl-infra/chef-repo/-/merge_requests/4628 (MR contains instructions for setting password)
- routing rule: https://gitlab.com/gitlab-com/gl-infra/chef-repo/-/merge_requests/4627
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Merge MR for k8s-workloads to set the Redis configurations - Set Redis config: gitlab-com/gl-infra/k8s-workloads/gitlab-com!3516 (merged)
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Merge MR for k8s-workloads to updating routing rules: gitlab-com/gl-infra/k8s-workloads/gitlab-com!3517 (merged) -
Merge MR for k8s-workloads to define a new shard: gitlab-com/gl-infra/k8s-workloads/gitlab-com!3518 (merged) - Verify that the
redis-sidekiq-catchall-a
instance starts receivingBRPOP
commands using thanos chart
- Verify that the
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Set label changecomplete /label ~change::complete
Rollback
Rollback steps - steps to be taken in the event of a need to rollback this change
Estimated Time to Complete (60 mins)
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Revert k8s-workload MR in the reverse order as required. i.e. if the new shard provisioned is breaking, revert that only. -
Set label changeaborted /label ~change::aborted
Monitoring
Key metrics to observe
- Metric: redis activity
- Location: thanos
- What changes to this metric should prompt a rollback: we should expect a steady
BRPOP
onredis-sidekiq-catchall-a
.
Change Reviewer checklist
-
Check if the following applies: - The scheduled day and time of execution of the change is appropriate.
- The change plan is technically accurate.
- The change plan includes estimated timing values based on previous testing.
- The change plan includes a viable rollback plan.
- The specified metrics/monitoring dashboards provide sufficient visibility for the change.
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Check if the following applies: - The complexity of the plan is appropriate for the corresponding risk of the change. (i.e. the plan contains clear details).
- The change plan includes success measures for all steps/milestones during the execution.
- The change adequately minimizes risk within the environment/service.
- The performance implications of executing the change are well-understood and documented.
- The specified metrics/monitoring dashboards provide sufficient visibility for the change.
- If not, is it possible (or necessary) to make changes to observability platforms for added visibility?
- The change has a primary and secondary SRE with knowledge of the details available during the change window.
- The change window has been agreed with Release Managers in advance of the change. If the change is planned for APAC hours, this issue has an agreed pre-change approval.
- The labels blocks deployments and/or blocks feature-flags are applied as necessary.
Change Technician checklist
-
Check if all items below are complete: - The change plan is technically accurate.
- This Change Issue is linked to the appropriate Issue and/or Epic
- Change has been tested in staging and results noted in a comment on this issue.
- A dry-run has been conducted and results noted in a comment on this issue.
- The change execution window respects the Production Change Lock periods.
- For C1 and C2 change issues, the change event is added to the GitLab Production calendar.
- For C1 and C2 change issues, the SRE on-call has been informed prior to change being rolled out. (In #production channel, mention
@sre-oncall
and this issue and await their acknowledgement.) - For C1 and C2 change issues, the SRE on-call provided approval with the eoc_approved label on the issue.
- For C1 and C2 change issues, the Infrastructure Manager provided approval with the manager_approved label on the issue.
- Release managers have been informed prior to any C1, C2, or blocks deployments change being rolled out. (In #production channel, mention
@release-managers
and this issue and await their acknowledgment.) - There are currently no active incidents that are severity1 or severity2
- If the change involves doing maintenance on a database host, an appropriate silence targeting the host(s) should be added for the duration of the change.
Edited by Sylvester Chin