Re: [hybi] Max frame size

Willy Tarreau <w@1wt.eu> Wed, 22 June 2011 12:25 UTC

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Date: Wed, 22 Jun 2011 14:25:21 +0200
From: Willy Tarreau <w@1wt.eu>
To: Francis Brosnan Blazquez <francis@aspl.es>
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Cc: hybi@ietf.org
Subject: Re: [hybi] Max frame size
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On Wed, Jun 22, 2011 at 12:33:31PM +0200, Francis Brosnan Blazquez wrote:
> Hi Willy,
> 
> > There is nothing in the protocol which makes whole frame buffering mandatory
> 
> I know, but I'm not talking about buffering, I'm talking about what to
> do when you receive more content than you can buffer. 
> 
> With the current design, the server have the following options: close
> the connection, or keep buffering or pass octects directly to the app
> level without having a frame header (with previous frame closed)...all 3
> options are really bad idea.

But why would it strip the frame header ? It should simply pass the frame
header and stream the data.

The server should proceed exactly as it would proceed if receiving a large
POST. All file transfer applications which support large POSTs (webmails
etc...) don't buffer everything, they pass it as a stream. Do you imagine
if the server had to buffer a DVD image or something like this before passing
it to the application ?

I don't see the difference with frames. You can call the application saying
"hey, here come 5 GB of data, please read them from this connection handle".

Regards,
Willy