Re: Reference set in HPACK

Greg Wilkins <gregw@intalio.com> Wed, 02 July 2014 07:39 UTC

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Date: Wed, 02 Jul 2014 09:37:23 +0200
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From: Greg Wilkins <gregw@intalio.com>
To: Roberto Peon <grmocg@gmail.com>
Cc: Kazu Yamamoto <kazu@iij.ad.jp>, HTTP Working Group <ietf-http-wg@w3.org>
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Subject: Re: Reference set in HPACK
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On 2 July 2014 08:09, Roberto Peon <grmocg@gmail.com> wrote:

> Even a few bytes per request adds up as the number of requests go up.
> Lets think about a page today that has 100 elements, which is something we
> see today.
> If the headers were regularized, with the use of a reference set, one
> could imagine a reduction of 20 bytes per header.
> With 100 elements, this is approximately 2k of data, or two packets worth.
>

Roberto,

I think this kind of calculation needs some real data.     Maintaining a
reference set is not a zero byte deal, as it still requires bytes to be
sent to remove entries from the reference set that are not needed.  If real
data shows that removals are frequent, then they may add up to close to the
2k also.

I don't think that it is unreasonable to request that realistic data is
provided to prove that a reference set is worthwhile.   It  would be good
to obtain and evaluate such data for both a single connection and coalesced
connections.

regards








-- 
Greg Wilkins <gregw@intalio.com>
http://eclipse.org/jetty HTTP, SPDY, Websocket server and client that scales
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