NetBSD/share/man/man9/hz.9

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.\" $NetBSD: hz.9,v 1.6 2008/04/30 13:10:58 martin Exp $
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.\" by Thomas Klausner.
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.Dd September 4, 2001
.Dt HZ 9
.Os
.Sh NAME
.Nm hz
.Nd system clock frequency
.Sh SYNOPSIS
.In sys/kernel.h
.Va int hz;
.Sh DESCRIPTION
.Nm
specifies the number of times the
.Xr hardclock 9
timer ticks per second.
.Nm
is hardware-dependent; it can be overridden (if the machine dependent
code supports this) by defining
.Em HZ
in the kernel configuration file (see
.Xr options 4 ) .
Only override the default value if you really know what you are
doing.
.Sh SEE ALSO
.Xr options 4 ,
.Xr callout 9 ,
.Xr hardclock 9 ,
.Xr microtime 9 ,
.Xr time_second 9