Accurate request time php web server and exact starting execution time in mysql db server

I got two servers One is application server on which PHP application is running and another server on which Mysql database is running. I want to measure time taken for the request send from application server to request received on database server for executing any query.

Note: The timestamp when request is just sent to database server and request which is received on database server before executing any query in response to the request. Interested in time required to transmit data between two servers.I know it depends on the size of data. I just want to get that time for different size of data.

kindly suggest If there is any tool for this kind to measurement or any method to do it for this specific request only.(Already know about request send timestamp only need to know how to capture request received timestamp)