Analysing your Web Server logs be it apache or IIS can be a big task and one well suited for tool such as awstats.

Awstats gives you a good overall view of traffic and stats for your site but a stat I always want to look at is requests per second as it has a direct correlation to CPU usage etc.

This will give you a more granular view of traffic and is especially useful for capacity management when it comes to API’s.

This script will parse your log file count the number of requests in each second and then add the results to an RRD file and produce a graph from that RRD file.

For this script to work the log file needs to be in the W3c standard format and so each line needs to start with a timestamp in the format yyyy-mm-dd hh:MM:ss.

It could be easily edited to use a different date format.

The below example will parse the log file “iislog.log”, create a graph named test.png.

The –createRRD is specified and so the test.rrd file will be created with a start time of 1320859514.

The graph will be 500px wide and 300px high with a title of “Requests Per Second”

./request.pl –logfile iislog.log –imageFileName test.png –rrdfile “test.rrd” –rrdGraphOptions “--width 500 --height 300 --title ‘Requests Per Second’” –createRRD –startEPOCH 1320859514

This will produce a graph like below: