Re: dont-revalidate Cache-Control header

Ben Maurer <ben.maurer@gmail.com> Mon, 13 July 2015 10:01 UTC

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Date: Mon, 13 Jul 2015 10:57:40 +0100
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From: Ben Maurer <ben.maurer@gmail.com>
To: Adam Rice <ricea@chromium.org>
Cc: Mark Nottingham <mnot@mnot.net>, Amos Jeffries <squid3@treenet.co.nz>, HTTP Working Group <ietf-http-wg@w3.org>
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Subject: Re: dont-revalidate Cache-Control header
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Hard to gather if "click reload to" in these cases is trying to get the
user to simply re-load the current URL or if they actually want the user to
change cache semantics. Maybe there's concrete data we could gather here.
For example, it would be amazing if we could get a UA to measure what % of
revalidations it sends result in not modified vs new content and if
resources with a distant expiration date that are forcibly revalidated via
a refresh are particularly unlikely to be refreshed. We could also study
this in the HTTP Archive -- if I took all resources that had a 30 day or
greater max age and send their servers revalidation requests 1 week from
today, what % of them return a 304 vs other responses.

That said, I completely understand why there would be hesitance to change
the semantics of this button given that it is implemented consistently
today across UAs -- it may be that the only way to implement this type of
behavior is a new CC header or an HTML tag to alter the behavior.



On Mon, Jul 13, 2015 at 9:23 AM, Adam Rice <ricea@chromium.org> wrote:

> On 12 July 2015 at 02:58, Ben Maurer <ben.maurer@gmail.com> wrote:
>
>> - Theoretically changes the behavior of a site which actively encourages
>> it's users to use the reload button (I've never seen such a site)
>
>
> https://www.google.com/search?q="click+reload+to"
>