Re: Deadlocking in the transport

Jana Iyengar <jri@google.com> Wed, 10 January 2018 20:04 UTC

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From: Jana Iyengar <jri@google.com>
Date: Wed, 10 Jan 2018 12:04:11 -0800
Message-ID: <CAGD1bZYiDOakLYNppMBr=99JreX3Xr2zkS7O2DRNfvr_o0NUbg@mail.gmail.com>
Subject: Re: Deadlocking in the transport
To: Jana Iyengar <jri@google.com>, "Charles 'Buck' Krasic" <ckrasic@google.com>, QUIC WG <quic@ietf.org>, Martin Thomson <martin.thomson@gmail.com>
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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?