In your php code insert some code that logs the request time, run time and reply time to see if a request is actually consuming time inside php. If you can conclude its delaying inside php code we can exclude nginx and search down the php line.
If its not php then compare the php logging you just made with nginx logging, if there are delays between nginx sending a request and php receiving them we can look there.
Etc.... without logging/testing at this level it will remain guesswork.
nb. maybe a local antivirus with firewall active?
If its not php then compare the php logging you just made with nginx logging, if there are delays between nginx sending a request and php receiving them we can look there.
Etc.... without logging/testing at this level it will remain guesswork.
nb. maybe a local antivirus with firewall active?