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Re: Question on flow control for a single file transfer

From: Peter Lepeska <bizzbyster@gmail.com>
Date: Sun, 3 Nov 2013 19:44:01 -0800
Message-ID: <CANmPAYH5m66qBUTj4XFYqiVRDZyxWy5qEeUKiZt1QkjLgrABbA@mail.gmail.com>
To: William Chan (陈智昌) <willchan@chromium.org>
Cc: Yoav Nir <ynir@checkpoint.com>, "<ietf-http-wg@w3.org>" <ietf-http-wg@w3.org>, Martin Thomson <martin.thomson@gmail.com>
Sloppiness? I don't get that. The sender's job is to transmit the data as
fast as possible, not to respect the receiver's best guesstimate of
available bandwidth sent ½ RTT ago. In this case, the sender's job is to
keep the TCP buffer full of data so it can send it when it has the
opportunity to.

Respecting the peer's receive window in the single file send case is
harmless at best and detrimental otherwise.

Peter
On Sunday, November 3, 2013, William Chan (陈智昌) wrote:

> I don't feel comfortable encouraging such sloppiness, I worry about future
> interop. Respecting a peer's receive window isn't hard. Just do it :)
>
> And even though wget doesn't support upload (to my knowledge, but I'm not
> an expert), a command line tool may upload, in which case it should
> definitely respect the peer's receive window.
> On Nov 3, 2013 6:22 PM, "Yoav Nir" <ynir@checkpoint.com<javascript:_e({}, 'cvml', 'ynir@checkpoint.com');>>
> wrote:
>
>>
>>  On Nov 3, 2013, at 1:25 PM, William Chan (陈智昌) <willchan@chromium.org<javascript:_e({}, 'cvml', 'willchan@chromium.org');>>
>> wrote:
>>
>>  It's probably understood already, but just to be clear, this is
>> receiver controlled and directional. Unless you control both endpoints, you
>> must implement flow control in order to respect the peer's receive windows,
>> even if you disable your own receive windows. Cheers.
>>
>>
>>  This discussion started with tools like WGET. If all you're ever sending
>> is one single request equivalent to "GET xxx", you're likely fine not
>> considering server receive window.
>>
>>  For a single file, the data that the client sends to the server never
>> exceeds the default server receive window.
>>
>>
>>
Received on Monday, 4 November 2013 03:44:28 UTC

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