Carlos Garnacho authored Nov 01, 2020 and Philip Withnall committed Nov 03, 2020

As hidden file caches currently work, every look up on a directory caches
its .hidden file contents, and sets a 5s timeout to prune the directory
from the cache.

This creates a problem for usecases like Tracker Miners, which is in the
business of inspecting as many files as possible from as many directories
as possible in the shortest time possible. One timeout is created for each
directory, which possibly means gobbling thousands of entries in the hidden
file cache. This adds as many GSources to the glib worker thread, with the
involved CPU overhead in iterating those in its main context.

To fix this, use a unique timeout that will keep running until the cache
is empty. This will keep the overhead constant with many files/folders
being queried.