Re: Deadlocking in the transport

Jana Iyengar <jri@google.com> Wed, 10 January 2018 20:32 UTC

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From: Jana Iyengar <jri@google.com>
Date: Wed, 10 Jan 2018 12:32:18 -0800
Message-ID: <CAGD1bZbPM3wnatLLN5938wGPo3e1qmxnGzobSTym6XX3W8FNJQ@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 12:23 PM, Dmitri Tikhonov <
dtikhonov@litespeedtech.com> wrote:

> 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.


I agree, but we aren't specifying the entire API, and I'm not sure that we
want to resolve all potential API inconsistencies here.

> 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?"


Yes, to avoid deadlock.


>
>   - Dmitri.
>