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Re: Deadlocking in the transport

Dmitri Tikhonov <dtikhonov@litespeedtech.com> Wed, 10 January 2018 20:24 UTC

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Date: Wed, 10 Jan 2018 15:23:57 -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 12:14:13PM -0800, Jana Iyengar wrote:
> SHOULD is pretty strong. It's not a guarantee, but then a transport
> implementation that doesn't do it is expected to know what it's doing.

If an application protocol is based on an assumption that the transport's
SHOULD is really a MUST, then you end up with an application that works
with some transport implementations, but not other -- conforming! --
implementations.

> We could include language in this section about priorities being important
> to avoid deadlocks when an application has dependencies across streams.

What would this advice be?  "Consume *all data* from higher priority
streams before consuming data from lower priority streams?"

  - Dmitri.

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