Ref T12319. Currently, we end up filtering archived packages out once for each path. This shows up on a profile from an install as meaningfully expensive:

https://secure.phabricator.com/xhprof/profile/PHID-FILE-7kmpevyr22aih4s2vyln/?symbol=PhabricatorOwnersPackage::isArchived

Instead, filter them out before we do any work.

Viewed a revision, still saw packages.