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Re: #131: Connection limits (proposal)

From: William A. Rowe, Jr. <wrowe@rowe-clan.net>
Date: Sun, 18 Oct 2009 23:01:54 -0500
Message-ID: <4ADBE4B2.9000204@rowe-clan.net>
To: Mark Nottingham <mnot@mnot.net>
CC: HTTP Working Group <ietf-http-wg@w3.org>
Mark Nottingham wrote:
> <http://trac.tools.ietf.org/wg/httpbis/trac/ticket/131>
> 
> NEW:
> 
> """
> Clients (including proxies) SHOULD limit the number of simultaneous
> connections that they maintain to a given server (including proxies).
> 
> Previous revisions of HTTP gave a specific number of connections as a
> ceiling, but this was found to be impractical for many applications. As
> a result, this specification does not mandate a particular maximum
> number of connections, but instead encourages clients to be conservative
> when opening multiple connections.
> 
> In particular, while using multiple connections avoids the "head-of-line
> blocking" problem (whereby a request that takes significant server-side
> processing and/or has a large payload can block subsequent requests on
> the same connection), each connection used consumes server resources
> (sometimes significantly), and furthermore using multiple connections
> can cause undesirable side effects in congested networks.
> """

Is it worthwhile to add the caveat;

"""
Clients attempting to establish simultaneous connections SHOULD anticipate
the server to reject excessive attempts to establish additional connections,
and gracefully degrade to passing all requests through the successfully
established connection(s), rather than retrying.
"""
Received on Monday, 19 October 2009 04:02:31 GMT

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