Having speed issues with a WordPress multi-site running on a dedicated server. The front end loads fine, but the WP Admin side takes a couple of minutes to load each page. Has happened since moving from one server to another (on the same network). New server has later versions of CentOS, PHP and MySQL.
I set up the P3 plugin to see if any plugins were causing the delay, but the main delay seems to be the WP Core loading (I'll update this when I can re-load the page to see how long it took).
I tried re-uploading a fresh download of the latest WP files but this didn't seem to help at all, so not sure if it's a DB issue.
Also, when trying to upgrade the network I'm getting this:
"Your server may not be able to connect to sites running on it. Error message: Connection timed out after 120001 milliseconds"
Edit: have now tried the Blackfire Profiler that @Steve mentioned in the comments and it's shown that the total load time for an admin page was 2 mins 1 second, with curl_exec() taking 2 minutes to process (99.6% of the processing time).
Does anyone know why this would take so long on the admin side?
Right - found out how to sort this using this Stack Overflow question after finding that curl_exec() was the major slowdown (using Blackfire as recommended by @Steve).
Basically just updated my /etc/hosts file so that the internal IP of the server points to the site URL and now it runs like a dream.