Why WordPress Multisite Admin Crawls at Scale and How I Fixed It
I recently chased a WordPress Multisite performance problem that made the admin feel unusable. Network screens like Sites and Plugins were taking about 20 seconds. That was on a healthy server and a database with no slow query alarms. It turned out to be a classic case of doing too much work on every admin request, hidden in a place most people do not look. The fix was small and the impact was huge. If you run a large multisite, this is worth checking.