org-agenda-ignore-drawer-properties

org-agenda-ignore-drawer-properties is a variable defined in `org.el'.
Its value is

nil

Documentation:
Avoid updating text properties when building the agenda.
Properties are used to prepare buffers for effort estimates, appointments,
and subtree-local categories.
If you don't use these in the agenda, you can add them to this list and
agenda building will be a bit faster.
The value is a list, with zero or more of the symbols `effort', `appt',
or `category'.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 24.3 of Emacs.