1*7a2ff9a0SSepherosa Ziehau.Dd February 17, 2014 2*7a2ff9a0SSepherosa Ziehau.Dt PERFBIAS 4 3*7a2ff9a0SSepherosa Ziehau.Os 4*7a2ff9a0SSepherosa Ziehau.Sh NAME 5*7a2ff9a0SSepherosa Ziehau.Nm perfbias 6*7a2ff9a0SSepherosa Ziehau.Nd device driver for Intel performance-energy bias support 7*7a2ff9a0SSepherosa Ziehau.Sh SYNOPSIS 8*7a2ff9a0SSepherosa ZiehauTo compile this driver into the kernel, 9*7a2ff9a0SSepherosa Ziehauplace the following line in your 10*7a2ff9a0SSepherosa Ziehaukernel configuration file: 11*7a2ff9a0SSepherosa Ziehau.Bd -ragged -offset indent 12*7a2ff9a0SSepherosa Ziehau.Cd "device perfbias" 13*7a2ff9a0SSepherosa Ziehau.Ed 14*7a2ff9a0SSepherosa Ziehau.Pp 15*7a2ff9a0SSepherosa ZiehauAlternatively, to load the driver as a 16*7a2ff9a0SSepherosa Ziehaumodule at boot time, place the following line in 17*7a2ff9a0SSepherosa Ziehau.Xr loader.conf 5 : 18*7a2ff9a0SSepherosa Ziehau.Bd -literal -offset indent 19*7a2ff9a0SSepherosa Ziehauperfbias_load="YES" 20*7a2ff9a0SSepherosa Ziehau.Ed 21*7a2ff9a0SSepherosa Ziehau.Sh DESCRIPTION 22*7a2ff9a0SSepherosa ZiehauThe 23*7a2ff9a0SSepherosa Ziehau.Nm 24*7a2ff9a0SSepherosa Ziehaudriver provides support for Intel performance-energy bias, 25*7a2ff9a0SSepherosa Ziehauwhich allows OS to guide logical CPU heuristic of power management features 26*7a2ff9a0SSepherosa Ziehauto favor increasing dynamic performance or conserve energy consumption. 27*7a2ff9a0SSepherosa ZiehauEach logical CPU could has its own performance-energy bias setting. 28*7a2ff9a0SSepherosa Ziehau.Sh MIB Variables 29*7a2ff9a0SSepherosa ZiehauEach logical CPU's performance-energy bias is controlled through the 30*7a2ff9a0SSepherosa Ziehau.Va machdep.perfbias Ns Em X 31*7a2ff9a0SSepherosa Ziehaubranch of the 32*7a2ff9a0SSepherosa Ziehau.Xr sysctl 3 33*7a2ff9a0SSepherosa ZiehauMIB. 34*7a2ff9a0SSepherosa Ziehau.Em X 35*7a2ff9a0SSepherosa Ziehauis the logical CPU id. 36*7a2ff9a0SSepherosa Ziehau.Bl -tag -width "hint" 37*7a2ff9a0SSepherosa Ziehau.It Va hint 38*7a2ff9a0SSepherosa ZiehauValid value ranges from 0 to 15, inclusive. 39*7a2ff9a0SSepherosa ZiehauSet it to 0 to give the highest performance. 40*7a2ff9a0SSepherosa ZiehauSet it to 15 to maximize energy saving. 41*7a2ff9a0SSepherosa Ziehau.El 42*7a2ff9a0SSepherosa Ziehau.Sh SEE ALSO 43*7a2ff9a0SSepherosa Ziehau.Xr sysctl 3 , 44*7a2ff9a0SSepherosa Ziehau.Xr sysctl 8 45