Re: Deadlocking in the transport

Dmitri Tikhonov <dtikhonov@litespeedtech.com> Wed, 10 January 2018 20:06 UTC

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Date: Wed, 10 Jan 2018 15:06:46 -0500
From: Dmitri Tikhonov <dtikhonov@litespeedtech.com>
To: Jana Iyengar <jri@google.com>
Cc: Charles 'Buck' Krasic <ckrasic@google.com>, QUIC WG <quic@ietf.org>, Martin Thomson <martin.thomson@gmail.com>
Subject: Re: Deadlocking in the transport
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On Wed, Jan 10, 2018 at 12:04:11PM -0800, Jana Iyengar wrote:
> On Wed, Jan 10, 2018 at 11:47 AM, Dmitri Tikhonov <
> dtikhonov@litespeedtech.com>; wrote:
> 
> > On Wed, Jan 10, 2018 at 11:34:11AM -0800, Jana Iyengar wrote:
> > > I agree. That's what I meant by priorities solving it -- that the shared
> > > resource (connection-level flow buffer), if consumed in priority order at
> > > the sender, avoids this deadlock. This  assumes that the application can
> > > express this to the transport of course.
> >
> > Even if the application can express it, the transport is not guaranteed
> > to consume the data in priority order: see the specification [1].
> 
> I don't see the text in that section that says otherwise. Under what
> conditions does the transport invert application stream priorities?

This is the text:

  " When deciding which streams to dedicate resources to, QUIC
  " SHOULD use the information provided by the application.
    ^^^^^^

  - Dmitri.