Is there a way to disable "Use Less CPU when in Background" for packaged program

how u guys determining cpu usage on packaged game?
are u using windows task manger or any stat command ?
i see no change of cpu usage on my packaged game. but in editor i have seen several cpu utilization related code

u may try “t.IdleWhenNotForeground=1” in the console.
but it most probably broken in 4.14 or 4.15
i have did a fix by altering engine side code. but as i said i never was able to detect any less cpu usage in package build.