24 Conserving Disk Space

24.1 Conserving Disk Space During Builds

To help conserve disk space during builds, you can add the following statement to your project’s local.conf configuration file found in the Build Directory:

INHERIT += "rm_work"

Adding this statement deletes the work directory used for building a recipe once the recipe is built. For more information on “rm_work”, see the rm_work class in the Yocto Project Reference Manual.

When you inherit this class and build a core-image-sato image for a qemux86-64 machine from an Ubuntu 22.04 x86-64 system, you end up with a final disk usage of 22 Gbytes instead of 90 Gbytes. However, 40 Gbytes of initial free disk space are still needed to create temporary files before they can be deleted.

24.2 Purging Duplicate Shared State Cache Files

After multiple build iterations, the Shared State (sstate) cache can contain duplicate cache files for a given package, while only the most recent one is likely to be reusable. The following command purges all but the newest sstate cache file for each package:

sstate-cache-management.sh --remove-duplicated --cache-dir=build/sstate-cache

This command will ask you to confirm the deletions it identifies.


The duplicated sstate cache files of one package must have the same architecture, which means that sstate cache files with multiple architectures are not considered as duplicate.

Run sstate-cache-management.sh for more details about this script.