@ -20,10 +20,9 @@ A cache today is immutable and cannot be updated. But some use cases require the
Reusing cache across feature branches is not allowed today to provide cache [isolation](https://docs.github.com/en/actions/using-workflows/caching-dependencies-to-speed-up-workflows#restrictions-for-accessing-a-cache). However if both feature branches are from the default branch, a good way to achieve this is to ensure that the default branch has a cache. This cache will then be consumable by both feature branches.
## Cross OS cache
From `v3.2.3` cache is crossos compatible when `enableCrossOsArchive` input is passed as true. This means that a cache created on `ubuntu-latest` can be used by `windows-latest` provided the workflow which runs on `windows-latest` have input `enableCrossOsArchive` as true. This is useful when you want to cache dependencies which are available on different the OSs. This will help reduce the consumption of the cache quota. Things to keep in mind while using this feature:
From `v3.2.3` cache is cross-os compatible when `enableCrossOsArchive` input is passed as true. This means that a cache created on `ubuntu-latest`or `mac-latest`can be used by `windows-latest` and vice versa, provided the workflow which runs on `windows-latest` have input `enableCrossOsArchive` as true. This is useful to cache dependencies which are independent of the runner platform. This will help reduce the consumption of the cache quota and help build for multiple platforms from the same cache. Things to keep in mind while using this feature:
- Only cache those files which are compatible across OSs.
- Caching symlinks might cause issues while restoration as they work differently on different OSs.
- Put runner OS in the cache key if that cache is not meant to be used across OSs to prevent cross-os.
## Force deletion of caches overriding default cache eviction policy
Caches have [branch scope restriction](https://docs.github.com/en/actions/using-workflows/caching-dependencies-to-speed-up-workflows#restrictions-for-accessing-a-cache) in place. This means that if caches for a specific branch are using a lot of storage quota, it may result into more frequently used caches from `default` branch getting thrashed. For example, if there are many pull requests happening on a repo and are creating caches, these cannot be used in default branch scope but will still occupy a lot of space till they get cleaned up by [eviction policy](https://docs.github.com/en/actions/using-workflows/caching-dependencies-to-speed-up-workflows#usage-limits-and-eviction-policy). But sometime we want to clean them up on a faster cadence so as to ensure default branch is not thrashing. In order to achieve this, [gh-actions-cache cli](https://github.com/actions/gh-actions-cache/) can be used to delete caches for specific branches.