These scripts allow for post-mortem analysis of an Apache access_log file to determine the number of requests per second. Normally this is graphed with something like mod_status and Munin. If you run into a situation where all you have is the access_log file, this will allow a reasonable approximation of what mod_status would have returned.
Note that apache_rps.sh requires bash 4.0+ due to the use of associative arrays.
$ ./apache_rps.sh <day> <access_log> <destination csv>
Day should be in the format of a date in your access_log, such as:
$ ./apache_rps.sh 01/Jun/2012 access_log 20120601.csv
Graphs are generated using R, where '100' is the maximum simultaneous connections your server is expected to support:
$ R --no-save --args 20120601.csv 100 < rps_daygraph.r
- Apache logs requests when they complete, not when they start. There's no way to reconstruct when requests start from the access_log.
- apache_rps.sh currently assumes that all of the logs from a given day are in a single uncompressed file. If they aren't, use grep and zgrep to create a single file to pass in.
- The bulk of the CSV generation is a simple line count. It should work with other similar log files from other web servers such as Varnish. It's only been tested with Apache in one specific configuration. Pull requests welcome!