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SubjectRe: jiffies rollover, uptime etc.
On Tue, Feb 19, 2002 at 12:55:22PM -0800, you [george anzinger] wrote:
> >
> > > Does this problem still exist on 64-bit machines?
> >
> > Absolutely. But not as often ;-)
>
> Actually you will have a VERY hard time getting it to roll over. Issues
> of your life time, not to mention the hardware's life time. 64 bits
> makes a VERY large number and you are counting in 427 day increments.
> Remember we have been counting seconds since 1970 in 32 bits and
> rollover is still, most likely, beyond the capability of any machine
> running today to get to. Now consider counting in 427 day increments
> instead of seconds.

48.5 day increments, not 497. On alpha and ia64 it's 1024 jiffies per
second.

Well, ok. Majority of the 64-bit archs seem to in fact use HZ=100:

asm-alpha/param.h:# define HZ 1024
asm-ia64/param.h:# define HZ 1024
asm-mips64/param.h:#define HZ 100
asm-ppc64/param.h:#define HZ 100
asm-s390x/param.h:#define HZ 100
asm-sparc64/param.h:#define HZ 100
asm-x86_64/param.h:#define HZ 100


-- v --

v@iki.fi
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