Re: Deadlocking in the transport

Dmitri Tikhonov <dtikhonov@litespeedtech.com> Wed, 10 January 2018 19:47 UTC

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Date: Wed, 10 Jan 2018 14:47:17 -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 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].

  - Dmitri.

1. https://tools.ietf.org/html/draft-ietf-quic-transport-08#section-10.6