This directory contains a collection of “golden” filesystem images that have been compressed with zstd.
These images are used to ensure that the latest version of Fxfs can continue to read filesystem images written by previous versions of the code.
The images themselves are generated with
fx fxfs create_golden by developers whenever the on-disk Fxfs version is changed. A unit test ensures this step is not forgotten and provides instructions if it is.
This is an auto-generated file. It is rewritten by
fx fxfs create_golden and includes all images found in the output directory.
It is required because our build system (GN) doesn't support wildcard dependencies but we need a way to ensure all images are included in tests run on CQ.
We have a hard requirement that an image exists for the current version of Fxfs but beyond that, engineers are free to manually remove old images as they see fit.