Add zstd workaround to README. Add yaml formatting to code blocks. Move Cache segment restore to Known Practices section.

This commit is contained in:
Lovepreet Singh 2022-08-25 13:14:23 +00:00
parent 7e7820edca
commit eb8b610ee6

@ -234,7 +234,7 @@ A cache gets downloaded in multiple segments of fixed sizes (`1GB` for a `32-bit
#### Update a cache #### Update a cache
A cache today is immutable and cannot be updated. But some use cases require the cache to be saved even though there was a "hit" during restore. To do so, use a `key` which is unique for every run and use `restore-keys` to restore the nearest cache. For example: A cache today is immutable and cannot be updated. But some use cases require the cache to be saved even though there was a "hit" during restore. To do so, use a `key` which is unique for every run and use `restore-keys` to restore the nearest cache. For example:
``` ```yaml
- name: update cache on every commit - name: update cache on every commit
uses: actions/cache@v3 uses: actions/cache@v3
with: with:
@ -248,6 +248,23 @@ A cache today is immutable and cannot be updated. But some use cases require the
#### Use cache across feature branches #### Use cache across feature branches
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. 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.
#### Improving cache restore performance on Windows
Currently, cache restore is slow on Windows due to both tar being slow and the compression algorithm being used is `gzip`. Zstd was disabled on windows due to issues with bsd tar(libarchive) which is the tar implementation in use on Windows. To improve cache restore performance, we can re-enable `zstd` as the compression algorithm using the following workaround by using GNU tar instead.
Add the following step to your workflow before the cache step:
```yaml
- if: ${{ runner.os == 'Windows' }}
name: Use GNU tar
shell: cmd
run: |
echo "Adding GNU tar to PATH"
echo C:\Program Files\Git\usr\bin>>"%GITHUB_PATH%"
```
This should work on all Github Hosted runners as it is. For self-hosted runners, please ensure you have GNU tar and `zstd` installed.
## Contributing ## Contributing
We would love for you to contribute to `actions/cache`, pull requests are welcome! Please see the [CONTRIBUTING.md](CONTRIBUTING.md) for more information. We would love for you to contribute to `actions/cache`, pull requests are welcome! Please see the [CONTRIBUTING.md](CONTRIBUTING.md) for more information.