Re: [quicwg/base-drafts] HTTP/3 with strict priorities (#2700)

Robin Marx <> Mon, 20 May 2019 16:19 UTC

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Subject: Re: [quicwg/base-drafts] HTTP/3 with strict priorities (#2700)
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Turns out I had misunderstood the intent of this PR with regards to @pmeenan's setup and how to recreate the following image. Turns out it's really quite brilliant! 

![pmeenan's approach](

For others who might not have figured it out:

@ianswett proposes to use odd numbered priority values (e.g., 127, 125, ...) to represent concurrency level 3, and even numbered priority values (e.g., 126, 124, ...) to represent concurrency levels 2 and 1.
For example:
127 = concurrency 3
126, no weight = concurrency 2
126, weight = concurrency 1

This allows the whole thing to be represented without a single placeholder (which I didn't understand before now)! That is immensely powerful, while also allowing normal placeholders.

It would also allow resolving #2690 in the same way as proposed in #2723 : just make priority 0, no weight the default for new nodes! 

We're not sure yet about streams-upon-streams dependencies and how this mixes with the placeholder approach etc. but it seems this PR could be the one we were looking for. We will iterate on this and create some example schema's. 

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