Re: HTTP/2 GREASE, Results, and Implications

On Thu, Oct 31, 2019 at 3:11 PM Willy Tarreau <w@1wt.eu> wrote:

> Hi David,
>
> On Thu, Oct 31, 2019 at 03:05:16PM -0400, David Benjamin wrote:
> > On Thu, Oct 31, 2019 at 1:18 PM Willy Tarreau <w@1wt.eu> wrote:
> >
> > > On Thu, Oct 31, 2019 at 01:08:53PM -0400, Bence Béky wrote:
> > > > Thanks, Willy, for pointing out the different sections of RFC7540
> > > > concerning unknown frame types.  It seems to me that for the past few
> > > days
> > > > Chrome (on certain channels) has been sending frames on half-closed
> > > > (remote) streams.  It might be worth fixing that and re-running the
> > > > experiment.  I'll circle back with results if we end up doing that.
> > >
> > > OK. I have a pending patch ready for testing on the haproxy front which
> > > addresses this mismatch. The only thing is that chrome beta doesn't
> seem
> > > to be available on linux so I constantly have to bother other people
> for
> > > testing, which takes time :-/
> > >
> >
> > Chrome beta (also dev channel) should be available on Linux. See
> > https://www.google.com/chrome/beta/?platform=linux. (Or if you've
> already
> > gotten the apt repository added, I believe the google-chrome-beta package
> > should work.) It also uses a separate profile directory, so it won't
> > conflict with your usual install. Hopefully that'll ease testing.
>
> Sorry I used the wrong word. The beta I download there is 78.something
> and does not match the latest one Yves was running (80 something). I
> tried it already and it doesn't fail. I also found "chrome dev" which
> is 79.something and doesn't present the problem either. When I go to
> the "chrome canary" link, it clearly says in the middle of the screen
> "we do not support linux". So for now I can't test, that's pretty sad :-/
>

Ah, gotcha. Yeah, we don't have a canary release for Linux sadly. Just
stable, beta, and dev. And, indeed, it looks like 80 hasn't made its way to
dev yet. :-/
https://chromiumdash.appspot.com/releases?platform=Linux

That said, it looks like we implemented GREASE for HTTP/2 quite a long time
ago. The experiment just wasn't enabled until now. You should be able to
force it on via a command-line flag on any remotely recent version. I'm not
sure off-hand what the incantation is. Bence?

David