TweakScheduler is a small utility originally conceived prior to 2009 as a small tool to adjust Win32PrioritySeparation registry value that controls if the foreground process (app that has focus) should receive longer CPU time slices than background processes, and if so, how much longer.

It has later been excluded as part of Process Lasso’s installer, in the ‘Options / Tools / Tweak Windows NT CPU scheduler parameters‘ menu item.

When using the defaults of ‘let the OS decide’, Windows Servers, by default, will give more time slices and length to background processes (being more fair to all), where-as Windows Workstations will lengthen and increase availability of time-slices to foreground processes.