system/config/log.php

Message logging is a very useful debugging tool for production websites, as well as a useful tool during development to see what files are being loaded in what order.

In production, it is recommended that you set disable "display_errors" in your index file, and set the logging threshold to log only errors.

threshold

Cascading message threshold.

Log Thresholds:

0
Disables logging completely
1
Error Messages (including PHP errors)
2
Debug Messages
3
Informational Messages

Default value: 1;

directory

Log file directory, relative to application/, or absolute.

Default value: 'logs';

format

PHP date format for timestamps.

Default value: 'Y-m-d H:i:s';