Re: MAX_CONCURRENT_STREAMS=0 and PUSH_PROMISE

Gábor Molnár <gabor.molnar@sch.bme.hu> Tue, 30 July 2013 08:31 UTC

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Date: Tue, 30 Jul 2013 10:26:11 +0200
From: Gábor Molnár <gabor.molnar@sch.bme.hu>
In-reply-to: <51F6D058.4010508@ogre.com>
To: Leif Hedstrom <leif@ogre.com>
Cc: Martin Thomson <martin.thomson@gmail.com>, Roberto Peon <grmocg@gmail.com>, Ilari Liusvaara <ilari.liusvaara@elisanet.fi>, HTTP Working Group <ietf-http-wg@w3.org>
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Subject: Re: MAX_CONCURRENT_STREAMS=0 and PUSH_PROMISE
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I'm OK with either solution (forbid push when max_streams=0 or signal
difference between two situations). From an implementation
perspective, I don't think many public server would support sending
PUSH_PROMISEs when they cannot push the actual content.

2013/7/29 Leif Hedstrom <leif@ogre.com>:
> On 7/24/13 1:43 AM, Martin Thomson wrote:
>>
>> On 23 July 2013 15:38, Roberto Peon <grmocg@gmail.com> wrote:
>>>
>>> I'm a proxy guy, actually.
>>
>>
>> I think that onus is on Roberto to more effectively motivate the need
>> for this distinction.
>>
>> If indeed we agree that the two cases are distinct, then we probably
>> need to consider ways to communicate this distinction effectively.  A
>> separate setting that expressly disables push promise or limits the
>> number of promises might work.
>>
>
> I'm very much in favor of this, be explicit about the client option to tell
> the server to never send push promises. It avoids any potential semantics
> overloading issues that we haven't yet foreseen. Plus, Roberto makes some
> pretty compelling arguments as to why it can make sense for a client to set
> MAX_CONCURRENT_STREAMS=0 but still want to see the push promises.
>
> -- Leif