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Re: Priority signals in HTTP/2

Martin Thomson <mt@lowentropy.net> Sun, 20 December 2020 23:10 UTC

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Date: Mon, 21 Dec 2020 10:09:22 +1100
From: Martin Thomson <mt@lowentropy.net>
To: Willy Tarreau <w@1wt.eu>
Cc: ietf-http-wg@w3.org
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Subject: Re: Priority signals in HTTP/2
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Hi Willy,

On Sun, Dec 20, 2020, at 04:04, Willy Tarreau wrote:
> I think I'm OK with this plan. I'm just thinking, do we have an exhaustive
> list of the most annoying problems caused by the current scheme and do we
> think that we could bring back some value if they were at least partially
> addressed ? If so, maybe we could have the following recommendations by
> order of preference:
>   - new priority scheme (yet to be defined)
>   - "fixed" version of the previous one to be used as a second option,
>     expected to work better than nothing with existing implementations;
>   - no priority handling at all (i.e. round robin or random)

I don't want to get too much into the shortcomings of the existing scheme, except for those things we know to be firmly true.  The only thing that I think can be said definitively is that attempting to send responses one at a time is better than trying to evenly share available capacity between multiple responses.

I expect that the new thing we ship will be much better than that, but it's probably best to let that specification speak for itself.

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