Re: HTTP/2 GREASE experiment results

Willy Tarreau <> Fri, 11 September 2020 17:41 UTC

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Date: Fri, 11 Sep 2020 19:38:38 +0200
From: Willy Tarreau <>
To: Bence =?iso-8859-1?Q?B=E9ky?= <>
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Subject: Re: HTTP/2 GREASE experiment results
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Hi Bence,

On Fri, Sep 11, 2020 at 12:00:49PM -0400, Bence Béky wrote:
> Here is a summary of recent HTTP/2 GREASE experiments in Chrome.  The
> findings can inform deployment of new HTTP/2 extensions.
> Overall I would say the ecosystem is in a pretty good shape when looking
> from the client side.

Thanks for the detailed report. I think this confirms the benefits of
GREASE, first to spot implementation bugs, and second also to spot
specification inconsistencies or conflicts if any. That's definitely
something to keep in mind for future specs, and probably that the
wording or advices regarding how to take care of this may result in
even simpler error handling rules. I admit that a few years ago I was
having a few doubts about the benefits, but given the low number of
remaining issues you've identified and how precise they are, it
certainly helps improve interoperability and upgradability a lot.