DavidR
9
Yes that is the case, confusion reigns - but the principal would be the same and was/is a quick way to see if there is an impact.
Yes it is going to place an additional resource load on your system, but many systems may be able to cope with that and an on-demand scan would be an extreme example (of testing it) and in not seeing any major I would hope that it would be the same for on-access scanning.
That said, it also brings a whole lot of other issues into the fray, such as what other applications are running (basic background resource use excluding avast), have you applied that to all avast shields that have it as an option. e.g. the web shield also has that as an option and that is possibly going to be the most active shield.
But given that you are experiencing high resource use I would set it back to the defaults and leave it at that.