What's the most precise way to calculate the time taken by my server to execute a HTTP request. I don’t want to know the DNS resolution or the traceroute time, but just the server execution time.
The is a follow up to my previous question to detect whats causing the delay between entering a domain name and load of the page
If you're using apache, you will need to monitor the %T value from the access logs. From the apache documentation:
"%T The time taken to serve the request, in seconds."
You can find more on apache log format here: http://httpd.apache.org/docs/2.2/mod/mod_log_config.html#formats
I think the best way to monitor HTTP traffic is to either Fiddler (free) or HTTPWatch (commercial) . These would really allow you to decode the traffic as well... THe god thing about these tools is that they even show you the response times
One way that will get you very close is to run a packet capture program on the server (Wireshark, for instance), start a capture and filter for HTTP traffic, access the web site from a client machine, stop the capture and look for the conversation between the client and the server and calculate the time between when the request got to the server and when the response left the server. This should give you the approximate time it took for the server to process the request.
In addition, if you're using IIS on Windows you could enable logging on the web site and look at the logs for a particular client\server session. This will tell you how long it took IIS to process the request. This should get you closer to your goal.
