The general outline of changes that require scheduling on the Deployments calendar.
| Anything that could make the cluster fall over
|
- Database schema changes
- Any change altering the databases schema must be asked on the schema changes page prior to deployment.
- Backend/underlying software updates (e.g. PHP, HHVM, MariaDB, etc.)
- Data-center changes (e.g. new DC coming online or datacenter going offline)
|
| Any notable production code change
|
- Out-of-sequence MediaWiki and extension code updates (including wikitech)
- BetaFeatures
- Anything going into BetaFeatures (new features for users)
- Anything going out of BetaFeatures (i.e. will now be user-default, or included in User Preferences)
- Adding a new extension (either cluster-wide or per wiki)
- Anything which introduces a new cookie (or renames an existing one)
- Big default behavior changes
|
| Anything requiring an outage/read-only
|
- Including on a per-wiki basis, like database shard migrations
|
| Anything with a high touch need/likelihood of breakage
|
- e.g. changes to deployment system
- changes that affect load characteristics substantially or in unknown ways, e.g. performance
- this section is informed by past breakages, as well
|
