Re: QPACK and the Static Table

Dmitri Tikhonov <dtikhonov@litespeedtech.com> Thu, 24 May 2018 18:21 UTC

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Date: Thu, 24 May 2018 14:20:56 -0400
From: Dmitri Tikhonov <dtikhonov@litespeedtech.com>
To: Roberto Peon <fenix@fb.com>
Cc: Willy Tarreau <w@1wt.eu>, Mike Bishop <mbishop@evequefou.be>, "quic@ietf.org" <quic@ietf.org>, HTTP Working Group <ietf-http-wg@w3.org>
Subject: Re: QPACK and the Static Table
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Mail-Followup-To: Roberto Peon <fenix@fb.com>, Willy Tarreau <w@1wt.eu>, Mike Bishop <mbishop@evequefou.be>, "quic@ietf.org" <quic@ietf.org>, HTTP Working Group <ietf-http-wg@w3.org>
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On Thu, May 24, 2018 at 05:53:14PM +0000, Roberto Peon wrote:
> One could make the lookup (more) efficient by storing the index (a
> byte at most) with the key-value pair, where the key-value pair were
> sorted via whatever sorting you'd find most efficient.  If reordering
> allows for some increased efficiency without increasing bits-on-wire,
> I'd think it seems reasonable to change.

Lookup efficiency should be a marginal consideration.  The table has
only a few dozen entries.  There are ways to compile the static table
to make lookups faster (for example, by using a perfect hash) if one
is bothered by doing a simple scan.

  - Dmitri.