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+.. SPDX-License-Identifier: CC-BY-SA-2.0-UK
+
+Conserving Disk Space
+*********************
+
+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 :term:`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 :ref:`ref-classes-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 &MIN_DISK_SPACE; Gbytes. However,
+&MIN_DISK_SPACE_RM_WORK; Gbytes of initial free disk space are still needed to
+create temporary files before they can be deleted.
+
+Purging Obsolete Shared State Cache Files
+=========================================
+
+After multiple build iterations, the Shared State (sstate) cache can contain
+multiple cache files for a given package, consuming a substantial amount of
+disk space. However, only the most recent ones are likely to be reused.
+
+The following command is a quick way to purge all the cache files which
+haven't been used for a least a specified number of days::
+
+   find build/sstate-cache -type f -mtime +$DAYS -delete
+
+The above command relies on the fact that BitBake touches the sstate cache
+files as it accesses them, when it has write access to the cache.
+
+You could use ``-atime`` instead of ``-mtime`` if the partition isn't mounted
+with the ``noatime`` option for a read only cache.
+
+For more advanced needs, OpenEmbedded-Core also offers a more elaborate
+command. It has the ability to purge all but the newest cache files on each
+architecture, and also to remove files that it considers unreachable by
+exploring a set of build configurations. However, this command
+requires a full build environment to be available and doesn't work well
+covering multiple releases. It won't work either on limited environments
+such as BSD based NAS::
+
+   sstate-cache-management.py --remove-duplicated --cache-dir=sstate-cache
+
+This command will ask you to confirm the deletions it identifies.
+Run ``sstate-cache-management.sh`` for more details about this script.
+
+.. note::
+
+   As this command is much more cautious and selective, removing only cache files,
+   it will execute much slower than the simple ``find`` command described above.
+   Therefore, it may not be your best option to trim huge cache directories.