Re: A structured format for dates?

Poul-Henning Kamp <phk@phk.freebsd.dk> Thu, 16 June 2022 05:48 UTC

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To: Mark Nottingham <mnot@mnot.net>
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Subject: Re: A structured format for dates?
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--------
Mark Nottingham writes:

> I'd love to hear what people think about this issue:
>   https://github.com/httpwg/http-extensions/issues/2162

I've added this comment:

	I see no mention of fractional seconds ?

	I think we need to ponder that, if the goal is (eventual) convergence for all timestamps in HTTP ?

	Considering how much effort we spend on speeding up HTTP, I find the "human readable" argument utterly bogus.

	Only a very tiny fraction of these timestamps are ever read by humans, and most are in a context where software trivially can render the number in 8601 format if so desired.

	In terms of efficiency, I will concede that, in a HTTP context, it is almost always possible to perform the necessary calculations and comparisons on raw ISO-8601 timestamps, without resorting to the full calendrical conversions, but once all the necessary paranoia is included, I doubt it is an optimization.

	My preference is sf-decimal seconds since epoch, (and this is largely why sf-decimal has three decimals in the first place), because it gives us fast processing, good compression and millisecond resolution.

	PS: A Twitter poll with only 40 respondents, carried out on the first monday after new-years ? Really ?!


-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.