Each ebuild in the Portage tree used to come with its own digest file. When you emerged a package, this digest was used to verify that you had the same files the developer did.

A few days ago, all digest files were erased from the Portage tree in CVS as part of the final work to implement GLEP 44. This migrates that information to a single Manifest file per package instead of one digest for every ebuild of that package. Portage hasn't been downloading these digest files for about a year, so this won't reduce the size of your tree again (it shrunk by ~200M at the time).

If you're still stuck on a Portage version in the 2.0.x series, follow the guide below on how to temporarily get Manifest1 files so you can update your Portage to the 2.1.x series.

References:

• Migrating back to Manifest1 for portage-2.0.x systems
• Understanding digest and manifest files
• GLEP 44: Manifest2 format
• [gentoo-dev] RFC: removal of digest files from the tree by Zac Medico
• [gentoo-dev] Redux: removal of digest files from the tree by Robin H. Johnson

Discuss this!

Łukasz Damentko and Joshua Nichols contributed the draft for this announcement.

Correction: This was just the final step in a long-term migration that actually reduced the size of your Portage tree last February. Thanks to Daniel Drake, Petteri Räty and Jan Kundrat for pointing this out.