The connection has timed out in developer mode

After I change developer mode to 1 in site json. I will do everything from mysql restart, bench migrate, restarting the vps and updating and clearing the cache. It seems to be just when developer mode is on but if I switch back to production mode then everything works fine. What can be done to fix this issue.

I changed it to this
“developer_mode”: 1,

Which operation times out? We need more information than this to figure out anything