- Gitian includes two caches where build-assets may be saved for use with
- subsequent builds. These caches are only enabled if the "enable_cache" key
- is enabled in the build descriptor.
- Common cache:
- All descriptors share this cache. It can be useful for storing fetched sources,
- sharing build assets between descriptors, etc.
- Per-descriptor cache
- Files installed to this cache can only be seen by this descriptor. Use this to
- store assets created as part of the build process, to avoid having to rebuild
- them in future builds.
- If caching is enabled, GBUILD_CACHE_ENABLED will be set to 1 in the build
- script. In addition, GBUILD_PACKAGE_CACHE and GBUILD_COMMON_CACHE will be set
- to their respective paths. GBUILD_PACKAGE_CACHE contains the descriptor's
- "name" key as a means of separating caches. To add or update the cached files,
- copy them to these paths.
- Before each build, all files and folders in the cache directories will be
- transferred to the VM. After each successful build, the caches will be
- transferred back to the builder (overwriting existing files as necessary).
- It is entirely up to the user and the descriptors to verify that cached files
- are actually suitable for re-use. Overwriting existing cached files is _highly_
- discouraged, as that would likely lead to non-deterministic results. Unique
- filenames should always be used.