From owner-freebsd-hackers  Wed Aug 18 10:40:21 1999
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From: Nate Williams <nate@mt.sri.com>
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To: Bill Studenmund <wrstuden@nas.nasa.gov>
Cc: Poul-Henning Kamp <phk@critter.freebsd.dk>,
	Terry Lambert <tlambert@primenet.com>, Hackers@FreeBSD.ORG
Subject: Re: BSD XFS Port & BSD VFS Rewrite 
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> > Both struct timespec and struct timeval are major mistakes, they
> > make arithmetic on timestamps an expensive operation.  Timestamps
> > should be stored as integers using an fix-point notations, for
> > instance 64bits with 32bit fractional seconds (the NTP timestamp),
> > or in the future 128/48.
...
> 
> > Extending from 64 to 128bits would be a cheap shift and increased
> > precision and range could go hand in hand.
> 
> I doubt we need more than 64 bit times. 2^63 seconds works out to
> 292,279,025,208 years, or 292 (american) billion years.

I think Poul's point is that in the future seconds is probably way too
coarse grained.  Computer's are getting faster all the time, and in the
future we may need 64 seconds, plus an additional 64 bits for the
fractions of a second, which will be necessary for accurate timekeeping.




Nate


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