64bit timestamp

deeptech71 at gmail.com deeptech71 at gmail.com
Fri Mar 23 19:31:05 UTC 2007


UNIX Timestamp:
   32 bits, starts from year 1970, ticks every second
   capable of representing the time from 1970 to 2106
   'til then, computers will change
   sufficient for file timestamps, comparing file times

Let's see what 64 bits can do!
2^64, that is 18446744073709551616 different values
18446744073709551616 / (1000000microseconds/value) / (60seconds/minute) / 
(60minutes/hour) / (24hours/day) / (365.2475days/year) / (2, for signed time 
values) = +-292273 years in the future/present, every microsecond

OK, presicion is too much, however, when very fast x64 computers are developed, 
programs should distinguish time between the same millisecond. Redunant for 
filesystems.. who would require 300K years? who would edit files every microsecond?

NTP has 136 years with such precision, that the processors these days cant handle.


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