SQL Server cached memory may be in the paging file on x64 or IA 64.

SQL Server cached memory may be in the paging file on x64 or IA 64.
Because 64bit platform has a lot of VAS.
So possible of SQL server's working set being paged out may increase.

You can protect this possible using a "Lock Pages in Memory" option on the group policy.
If you configure the option, it will be protect being paged out.

Source : http://nexondbteam.tistory.com/38