Re: #38 - HTTP2 min value for server supported max_concurrent_streams

Yoav Nir <ynir@checkpoint.com> Fri, 22 February 2013 09:48 UTC

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From: Yoav Nir <ynir@checkpoint.com>
To: Osama Mazahir <OSAMAM@microsoft.com>
CC: "ietf-http-wg@w3.org Group" <ietf-http-wg@w3.org>
Thread-Topic: #38 - HTTP2 min value for server supported max_concurrent_streams
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Date: Fri, 22 Feb 2013 09:47:08 +0000
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Subject: Re: #38 - HTTP2 min value for server supported max_concurrent_streams
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Hi Osama

Wouldn't 1 be a better initial value?  This would allow minimal implementations with no concurrency at all. It's usually the case for browser that the first round-trip contains exactly one request (for the HTML file), and only when the response is received do more requests come out. So this wouldn't slow us down much.

Yoav

On Feb 22, 2013, at 7:00 AM, Osama Mazahir <OSAMAM@microsoft.com> wrote:

> Hi,
> 
> Issue #38 [1] tracks:
> 	(1) What is the minimum number of concurrent client-initiated streams that a server must be able to support?
> 	(2) What is the default value?
> 
> We have a race condition where the client can initiate more streams to the server before the server can advertise its stream accept limit to the client.  I suggest making the default the same as the minimum so that we can prevent that race.  And tighten the wording on what is legal.  For example, something like:
> 
> A server MUST be able to handle at least 8 concurrent streams initiated by the client. A server MUST NOT advertise a value less than 8. A client MUST generate a session error if it receives a value less than 8 from the server. The default value server limit is 8.
> 
> Thanks,
> --Osama.
> 
> [1] https://github.com/http2/http2-spec/issues/38