This article discussed removal of the “var/log/system.log” Magento log file. You can find this file in your Magento installation path. A command such as the following would help:
find /var/www -name "system.log"
Tip: replace “/var/www” with the path to your Magento installation.
Removing the “system.log” file has no effect from what i can tell. I’ve found this file to be quiet large on popular sites. Ideally it would be included in “logrotate”. Here’s some discussions on this topic “http://magento.stackexchange.com/questions/52953/delete-system-log-file” and “http://stackoverflow.com/questions/25752519/system-log-and-exception-log-size-and-maintenance”.