Increase the Database Read Marking Limit to 14 or 21?
 

We would like to increase the Database Read Marking Limit from 10 to 14 (two weeks) or 21 (three weeks) but we don´t know if we dare. What is your experience regarding increasing this number?

I have a feeling that the Thread/Forum Read Marking Type option we use today is very processor intensive. We use the option Database (automatic forum marking).