woodpecker/docs/build/cache.md

Caching

This feature is still considered experimental

Drone allows you to cache directories within the build workspace. When a build successfully completes, the named directories are gzipped and stored on the host machine. When a new build starts, the named directories are restored from the gzipped files. This can be used to improve the performance of your builds.

Below is an example .drone.yml configured to cache the .git and the node_modules directory:

cache:
  mount:
    - node_modules
    - .git

Branches and Matrix

Drone keeps a separate cache for each Branch and Matrix combination. Let's say, for example, you are using matrix builds to test node 0.11.x and node 0.12.x and you are caching node_modules. Drone will separately cache node_modules for each version of node.

Pull Requests

Pull requests have read-only access to the cache. This means pull requests are not permitted to re-build the cache. This is done for security and stability purposes, to prevent a pull request from corrupting your cache.

Deleting the Cache

There is currently no mechanism to automatically delete or flush the cache. This must be done manually, on each worker node. The cache is located in /var/lib/drone/cache/.

Distributed Cache

This is outside the scope of Drone. You may, for example, use a distributed filesystem such as ceph or gluster mounted to /var/lib/drone/cache/ to share the cache across nodes.