This is regarding the Tomcat's access log pattern variables:

As per Apache's doc: %D - Time taken to process the request, in millis %F - Time taken to commit the response, in millis

What do they actually mean?

According to my understanding,

%D = time taken by tomcat between receiving the first byte of the request and sending out the last response byte

%F = time taken by tomcat between receiving the last byte of the request and sending out the first response byte

Is this correct??

1 Answers

1
Mark Thomas On Best Solutions

%D is the time from when Tomcat reads the first byte of the request until the last response byte has been written.

%F is the time from when Tomcat reads the first byte of the request until the first byte of the response is written to the client.

Note that the time the first byte is read may be a little after the time that byte is received due to network buffering (particularly under load) or HTTP pipe-lining (if the client uses it - most don't).