The Optimise File Scans option: Optimise file scans to run much faster

The Optimise File Scans option is a part of the Hack Guard module. The setting can be found under the Scan Options and is enabled by default:

Significant optimisation in file scanning with reduction of full file scan times by up to 66%. For example, if a file scan would have normally lasted for 3 minutes, it'll now take less than 1 minute. This means that, when you use the Optimise File Scans option, you'll get faster scanning, less waiting, and much lighter load on your servers by using fewer resources. 

Important: If you experience any errors in your logs or strange scanning behaviour, disable this option.