Consider the parameter A used

When A is set to a small value, then the set of resident pages for a process might be underestimated allowing a process to be scheduled even though all of its required pages are not resident. This could result in a large number of page faults. When A is set to a large value, then a process's resident set is overestimated and this might prevent many processes from being scheduled even though their required pages are resident. However, once a process is scheduled, it is unlikely to generate page faults since its resident set has been overestimated.