W3C home > Mailing lists > Public > ietf-http-wg@w3.org > January to March 2009

Re: Extension headers and caching

From: Julian Reschke <julian.reschke@gmx.de>
Date: Tue, 10 Feb 2009 19:08:34 +0100
Message-ID: <4991C2A2.7060205@gmx.de>
To: Eric Lawrence <ericlaw@exchange.microsoft.com>
CC: Anne van Kesteren <annevk@opera.com>, HTTP Working Group <ietf-http-wg@w3.org>

Eric Lawrence wrote:
>> IE has lots of issues with Vary
> To be more specific, the WinINET networking stack does not cache outbound request headers, preventing IE and other applications from reusing resources that Vary without validation (except in narrow cases).  See http://www.fiddler2.com/fiddler/Perf/AboutVary.asp for more information.
> Revalidation ensures cache-correctness but entails a performance cost.
> -Eric

As far as I recall it also means that you can't pass content with Vary: 
to an external application, such as an *ics file (IE invokes the 
application with a filename of a temp file that does not exist). This is 
as of IE6, maybe it has been fixed since.

BR, Julian
Received on Tuesday, 10 February 2009 18:09:23 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 1 March 2016 11:10:48 UTC