Enable PackObjectsHookWithSidechannel in gprd

Production Change

Change Summary

Enable the gitaly_pack_objects_hook_with_sidechannel feature flag in gprd. This will route existing PackObjectsHook gRPC traffic to use PackObjectsHookWithSidechannel instead. The new RPC uses less CPU.

Already enabled in staging: #5422 (closed)

Change Details

1. Services Impacted - ServiceGitaly
2. Change Technician - @jacobvosmaer-gitlab
3. Change Reviewer - DRI for the review of this change
4. Time tracking - 60m
5. Downtime Component - no downtime

Detailed steps for the change

Pre-Change Steps - steps to be completed before execution of the change

Estimated Time to Complete (mins) - 10m

• Set label changein-progress on this issue
• git clone --depth=1 --bare git@gitlab.com:gitlab-org/gitlab.git test.git
• git clone --depth=1 --bare https://gitlab.com/gitlab-org/gitlab.git test.git

Change Steps - steps to take to execute the change

Estimated Time to Complete (mins) - 30m

• /chatops run feature set gitaly_pack_objects_hook_with_sidechannel true --project=gitlab-org/gitlab
• git clone --depth=1 --bare git@gitlab.com:gitlab-org/gitlab.git test.git
• git clone --depth=1 --bare https://gitlab.com/gitlab-org/gitlab.git test.git
• /chatops run feature delete gitaly_pack_objects_hook_with_sidechannel
• /chatops run feature set gitaly_pack_objects_hook_with_sidechannel 1
• /chatops run feature set gitaly_pack_objects_hook_with_sidechannel 10
• /chatops run feature set gitaly_pack_objects_hook_with_sidechannel 100

Post-Change Steps - steps to take to verify the change

Estimated Time to Complete (mins) - 20m

• Observe RPC dashboard
• Observe logs

Rollback

Rollback steps - steps to be taken in the event of a need to rollback this change

Estimated Time to Complete (mins) - 5m

• /chatops run feature delete gitaly_pack_objects_hook_with_sidechannel

Monitoring

Key metrics to observe

• Metric: Gitaly error rate
  • Location: https://dashboards.gitlab.net/d/gitaly-main/gitaly-overview?orgId=1&var-PROMETHEUS_DS=Global&var-environment=gprd&var-stage=main
  • What changes to this metric should prompt a rollback: increase in errors
• Metric: Gitaly apdex
  • Location: https://dashboards.gitlab.net/d/gitaly-main/gitaly-overview?orgId=1&var-PROMETHEUS_DS=Global&var-environment=gprd&var-stage=main
  • What changes to this metric should prompt a rollback: decrease in apdex score
• Metric: PackObjectsHookWithSidechannel error rate and apdex
  • Location: https://dashboards.gitlab.net/d/000000199/gitaly-feature-status?orgId=1&refresh=30s&var-environment=gprd&var-method=PackObjectsHookWithSidechannel&var-prometheus=prometheus-01-inf-gprd
  • What changes to this metric should prompt a rollback: decrease in apdex score, increase in errors

Summary of infrastructure changes

• Does this change introduce new compute instances? NO
• Does this change re-size any existing compute instances? NO
• Does this change introduce any additional usage of tooling like Elastic Search, CDNs, Cloudflare, etc? NO

Changes checklist

• This issue has a criticality label (e.g. C1, C2, C3, C4) and a change-type label (e.g. changeunscheduled, changescheduled) based on the Change Management Criticalities.
• This issue has the change technician as the assignee.
• Pre-Change, Change, Post-Change, and Rollback steps and have been filled out and reviewed.
• This Change Issue is linked to the appropriate Issue and/or Epic
• Necessary approvals have been completed based on the Change Management Workflow.
• 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.
• 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.)
• Release managers have been informed (If needed! Cases include DB change) prior to change being rolled out. (In #production channel, mention @release-managers and this issue and await their acknowledgment.)
• There are currently no active incidents