Hi,
The Grimlock Query Section Block can cause poor performance in multi-site installations with a large number of sites (e.g. > 100).
The following function is run on every admin page request, regardless of what you are doing:
\Grimlock_Query_Section_Block::add_site_field()
The function loops through every site and runs current_user_can_for_blog(), which will run switch_to_blog(). Other plugins often hook into those two function calls, so a lot of unnecessary calls are taking place.
Is it possible to ensure the field configuration options for blocks are only loaded when necessary rather than on every page?
Thanks.