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   mcc (mcc@mastodon.social)'s status on Friday, 15-Mar-2024 12:44:44 JST mcc

   Me when I use a uint64_t to represent time in my application

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     ✧✦✶✷Catherine✷✶✦✧ (whitequark@mastodon.social)'s status on Friday, 15-Mar-2024 12:44:51 JST ✧✦✶✷Catherine✷✶✦✧

     in reply to

     @mcc but is it seconds? nanoseconds? femtoseconds?

     in CXXRTL i use single femtoseconds as the timebase and boy, does 64-bit time look short when you do that

     (I ended up having a 128-bit cxxrtl::time that is converted to 64.64 fixed point when communicating to other applications)

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     mcc (mcc@mastodon.social)'s status on Friday, 15-Mar-2024 12:44:55 JST mcc

     in reply to

     • ✧✦✶✷Catherine✷✶✦✧

     @whitequark I actually worked this out and in order for a program launched in 2023 and tracking time in a 64-bit variable to create a problem in 3193, the time unit would have to be "ticks" of 4 nanoseconds. Additionally, you would need somewhere to cast the to an int64_t or otherwise subtract it in such a way the highest bit is assumed unset.

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     Richard Hendricks (hendric@astronomy.city)'s status on Friday, 15-Mar-2024 12:44:55 JST Richard Hendricks

     in reply to

     • ✧✦✶✷Catherine✷✶✦✧

     @mcc @whitequark ...pulls out my proposal to use 256 bit timers with Planck time ticks of 5e-44 s - good for 35 thousand trillion years!

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     Farce Majeure (vathpela@better.boston)'s status on Friday, 15-Mar-2024 12:45:00 JST Farce Majeure

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     • ✧✦✶✷Catherine✷✶✦✧

     @mcc @whitequark ... Which sounds ridiculous, but the part of me that knows FAT filesystems have 2 second granularity knows someone will do it.

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     Tom Forsyth (tomf@mastodon.gamedev.place)'s status on Friday, 15-Mar-2024 12:45:07 JST Tom Forsyth

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     • ✧✦✶✷Catherine✷✶✦✧

     @mcc @whitequark Highly recommend you take a look at (and then steal) the NTP format:
     https://en.wikipedia.org/wiki/Network_Time_Protocol

     They also have a 128-bit version that seems... adequate:

     "enough to resolve the amount of time it takes a photon to pass an electron at the speed of light. [...] enough to provide unambiguous time representation until the universe goes dim."

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     mcc (mcc@mastodon.social)'s status on Friday, 15-Mar-2024 12:45:13 JST mcc

     in reply to

     Do this

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