Re: Proposal - Reduce HTTP2 frame length from 16 to 12 bits

Patrick McManus <mcmanus@ducksong.com> Tue, 28 May 2013 20:35 UTC

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Date: Tue, 28 May 2013 16:33:29 -0400
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From: Patrick McManus <mcmanus@ducksong.com>
To: Roberto Peon <grmocg@gmail.com>
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Subject: Re: Proposal - Reduce HTTP2 frame length from 16 to 12 bits
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On Tue, May 28, 2013 at 4:12 PM, Roberto Peon <grmocg@gmail.com> wrote:

My sweet-spot number was 16k, as I knew that I could saturate a 10G nic
> with 16k frames/writes and have enough CPU left over to do some actual
> work. The amount of overhead goes up more than linearly with the decrease
> in frame size thanks to contention, etc.
>
>

Given what you've said here and in the other mail (plus of course my own
previously stated concerns) I'm inclined to suggest a 16KB max (14 bits)
without introducing any kind of max frame size configurable. My point is to
drive it as small as we can without creating excessive overhead and you've
put a stake in the ground that 16KB is that level. That's still 4x as
aggressive as the current draft.