Re: How long is a hz?
Jason Slagle wrote: On Mon, 28 Jan 2008, Sean Bruno wrote: I couldn't quite find the definition for hz in sys/ this morning. What is it's value and where is it defined? From http://en.wikipedia.org/wiki/Hertz The hertz (symbol: Hz) is the International System of Units (SI) base unit of frequency. Its base unit is cycle/s or s^-1 (also called inverse seconds, reciprocal seconds). In English, hertz is used as both singular and plural. As any SI unit, Hz can be prefixed; commonly used multiples are kHz (kilohertz, 10^3 Hz), MHz (megahertz, 10^6 Hz), GHz (gigahertz, 10^9 Hz) and THz (terahertz, 10^12 Hz). One hertz simply means one cycle per second (typically that which is being counted is a complete cycle); 100 Hz means one hundred cycles per second, and so on. The unit may be applied to any periodic event--for example, a clock might be said to tick at 1 Hz, or a human heart might be said to beat at 1.2 Hz. The frequencies of aperiodic events, such as radioactive decay, are expressed in becquerels. But more importantly, where is hz defined in the kernel tree? Sean ___ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: How long is a hz?
Sean Bruno wrote: Jason Slagle wrote: On Mon, 28 Jan 2008, Sean Bruno wrote: I couldn't quite find the definition for hz in sys/ this morning. What is it's value and where is it defined? From http://en.wikipedia.org/wiki/Hertz The hertz (symbol: Hz) is the International System of Units (SI) base unit of frequency. Its base unit is cycle/s or s^-1 (also called inverse seconds, reciprocal seconds). In English, hertz is used as both singular and plural. As any SI unit, Hz can be prefixed; commonly used multiples are kHz (kilohertz, 10^3 Hz), MHz (megahertz, 10^6 Hz), GHz (gigahertz, 10^9 Hz) and THz (terahertz, 10^12 Hz). One hertz simply means one cycle per second (typically that which is being counted is a complete cycle); 100 Hz means one hundred cycles per second, and so on. The unit may be applied to any periodic event--for example, a clock might be said to tick at 1 Hz, or a human heart might be said to beat at 1.2 Hz. The frequencies of aperiodic events, such as radioactive decay, are expressed in becquerels. But more importantly, where is hz defined in the kernel tree? Sean ___ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to [EMAIL PROTECTED] http://fxr.watson.org/fxr/ident?i=hz ___ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: How long is a hz?
On Monday 28 January 2008, Sean Bruno wrote: I couldn't quite find the definition for hz in sys/ this morning. What is it's value and where is it defined? sys/kern/subr_param.c:int hz; sys/sys/time.h: int hz; /* clock frequency */ sys/kernel.h:extern int tick; /* usec per tick (100 / hz) */ sys/kernel.h:extern int hz; /* system clock's frequency */ The actual value for hz comes from your kernel configuration. The default is options HZ=1000 at the moment. -- /\ Best regards, | [EMAIL PROTECTED] \ / Max Laier | ICQ #67774661 X http://pf4freebsd.love2party.net/ | [EMAIL PROTECTED] / \ ASCII Ribbon Campaign | Against HTML Mail and News signature.asc Description: This is a digitally signed message part.
Re: How long is a hz?
Sam Leffler wrote: Sean Bruno wrote: Jason Slagle wrote: On Mon, 28 Jan 2008, Sean Bruno wrote: I couldn't quite find the definition for hz in sys/ this morning. What is it's value and where is it defined? http://fxr.watson.org/fxr/ident?i=hz Thank you Sam. You have taught me how to fish as it were. The answer that I was searching for is located at: http://fxr.watson.org/fxr/source/kern/subr_param.c#L56 Sean ___ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to [EMAIL PROTECTED]
