Messages in this thread |  | | Date | 08 Jun 1999 20:00:00 +0200 | | From | (Kai Henningsen) | | Subject | Re: Migrating to larger numbers |
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hagopiar@vuser.vu.union.edu wrote on 01.06.99 in <Pine.LNX.4.10.9906011723020.6925-100000@sequoia.hagopian.net>:
> Sure, it would be nice, but so would a 128-bit value. That would solve > time problems for quite a while, but it's just not practical. That's why > Sun went the way of fixing it for 64-bit machines and letting the 32-bit > machines fall to the wayside.
Well, let's see what you'd want to have for the long run.
You want to be able to cover a range of around 100e9 years (several times the current age of the universe), in seconds that's approximately 61 bits. And for resolution, you probably want at least nanoseconds (that's only 1 GHz, in a few years cycle counters will probably run faster than that), that's 1e9 or about 30 bits.
91 bit together, might as well use 96 (64+32).
2^64 seconds are over 500e9 years (better use 250 signed), and 1/2^32 seconds are about a quarter nanosecond. Sounds about right.
Now, that's for the interface. What's used internally is a completely different question.
MfG Kai
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