RE: Submitted new I-D: Cache Digests for HTTP/2

You’re correct – I see the same in Chrome; haven’t tried Firefox or sanity-checked the DNS records.  Anyone from the Googly side want to weigh in?

From: Alcides Viamontes E [mailto:alcidesv@zunzun.se]
Sent: Monday, April 11, 2016 8:32 AM
To: Mike Bishop <Michael.Bishop@microsoft.com>
Cc: Martin Thomson <martin.thomson@gmail.com>; Kazuho Oku <kazuhooku@gmail.com>; HTTP Working Group <ietf-http-wg@w3.org>
Subject: Re: Submitted new I-D: Cache Digests for HTTP/2

Thanks Mike,

Can you point to any public-facing website  where connection coalescing   is working?

We haven't been lucky at configuring connection coalescing in our website and that have led me to believe (perhaps mistakenly) that browsers don't implement it yet. This page ( https://www.shimmercat.com/en/blog/articles/data-density/ )  for example pulls resources from three subdomains on the same wildcard certificate, same web server. Chrome creates a separate connection* for each of them (seen by looking to chrome://net-internals, also confirmed by looking to the logs of ShimmerCat). As a side-note, we use SANs at development, and there there is no coalescing either. Same situation with Firefox.

* Actually Chrome opens  an entire connection pool for media.shimmercat.com<http://media.shimmercat.com> with six sockets, of which only one is used.

On Mon, Apr 11, 2016 at 4:57 PM, Mike Bishop <Michael.Bishop@microsoft.com<mailto:Michael.Bishop@microsoft.com>> wrote:
I believe that Chrome and Firefox coalesce when DNS/SANs permit.  Edge/IE currently does not.

From: Alcides Viamontes E [mailto:alcidesv@zunzun.se<mailto:alcidesv@zunzun.se>]
Sent: Sunday, April 10, 2016 1:16 AM
To: Martin Thomson <martin.thomson@gmail.com<mailto:martin.thomson@gmail.com>>
Cc: Kazuho Oku <kazuhooku@gmail.com<mailto:kazuhooku@gmail.com>>; HTTP Working Group <ietf-http-wg@w3.org<mailto:ietf-http-wg@w3.org>>
Subject: Re: Submitted new I-D: Cache Digests for HTTP/2

Hello Martin,

We will take a closer look at this. But what is the state of coalescing regarding browser implementations?

On Fri, Apr 8, 2016 at 3:53 PM, Martin Thomson <martin.thomson@gmail.com<mailto:martin.thomson@gmail.com>> wrote:
On 8 April 2016 at 10:44, Kazuho Oku <kazuhooku@gmail.com<mailto:kazuhooku@gmail.com>> wrote:
> So the question boils down to two.
>
> Q1. How many fresh resources exist per origin?

> Q2. What is the appropriate value for P?

I have some others:

What is the effect of connection coalescing on this? When coalescing,
Is a client better off sending a separate digest for each origin, or
is a single large blob better?