[LEAPSECS] Lets get REAL about time.

Bob Paddock bob.paddock at gmail.com
Sun Jan 22 11:02:45 EST 2012

On Fri, Jan 20, 2012 at 6:29 AM, Poul-Henning Kamp <phk at phk.freebsd.dk> wrote:

> Modern CPUs clock around 4GHz, multiplying by 1000 for resulution we

> find that we need 42 bits after the binary point.

>IEEE binary128 floatingpoint

I take issues with hardware requiring those kind of resources to keep
track of time.
There are more Embedded Systems today running at well under 100 MHz (or 10 MHz),
and 128 Floating Point on them just isn't going to happen.
These systems do need to keep accurate time just as the bigger systems do.

> 77 bits is pretty far from 64 bits, and already today, 42 years

> from our epoch, 64bit resolution have 4% error on nanoseconds,

> that's not workable.

Don't know that it helps your goal, there is already LibTAI
http://cr.yp.to/libtai.html :

"TAI64, covering a few hundred billion years with 1-second precision;
(2) TAI64NA, covering the same period with 1-attosecond precision"


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