Extremely slow backend after update

Hello,

I am experiencing extremely slow backend since updating to the latest version. I was using a 4.6.x version and I switch to 4.7.2 two days ago which is a nightmare ever since. Front end works fine, it’s not a hosting issue. I tried disabling all plugins and switching to a default theme to no avail. This is a core issue and I have seen other people reportng this as well.

Can a pro/dev etc look into this and diagnose why this is happening please? Queries take forever on the backend while front end works fine. My website became literally unmanageable since updating to the latest version.

Please help!