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Re: bohe and delta experimentation...

"Poul-Henning Kamp" <phk@phk.freebsd.dk> Thu, 17 January 2013 11:05 UTC

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To: James M Snell <jasnell@gmail.com>
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From: Poul-Henning Kamp <phk@phk.freebsd.dk>
References: <CABP7RbeNFm3ZHdtDBUJb3idJjFj0q+fxDPzxKZBhSJqXw8zWaQ@mail.gmail.com>
Date: Thu, 17 Jan 2013 11:03:11 +0000
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Subject: Re: bohe and delta experimentation...
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--------
In message <CABP7RbeNFm3ZHdtDBUJb3idJjFj0q+fxDPzxKZBhSJqXw8zWaQ@mail.gmail.com>
, James M Snell writes:

>I'm starting with dates first...

>Then, given a sample of 100k
>more randomly generated timestamps, the average compression was 12-13 bytes
>for the date value.

<hat="Certified Time Nut">

With an 8 bytes fixed field, you could have 2 billion years with
~4 msec resolution if you just packed it as a binary number.

As a bonus, it's cheap to work with in computers...

If you do leading zero suppression it will be only five bytes for
most of the first century.

Please also loose any and all mention of timezones:  All timestamps
SHALL be UTC in HTTP, we do really not want to have to keep track
of fickle politicians fudging timezones on our load-balancers.

</hat>

-- 
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.

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