Re: Quoting email (was: HTTP/2 and TCP CWND)

Another attempt


>>On 4/16/13 12:03 PM, "Roberto Peon"
>><grmocg@gmail.com<mailto:grmocg@gmail.com>> wrote:
>>
>> Unfortunately, most flows with http/1 are short (and bursty) flows, so
>>it is incorrect to say that they have reached steady-state w.r.t.
>>congestion control. Many resource fetches complete in between one and
>>three rtts, then much of time the connection(s) sit idle for extended
>>periods of time (seconds to minutes).

Good point.  Most of my work with HTTP/1 (and TCP) are with long-lived
flows and I live in the long tail.  My gut tells me you are correct when
it comes to traditional web usage.

>> I'm hoping Will will chime in here with data soon, but the distribution
>>on single connection cwnds as measured on traffic in the wild shows us
>>that using multiple connections puts more packets on the wire as a
>>result of init-cwnd (and thus not subject to congestion control, ouch)
>>than a single stable-state, heavily used and reused connection such as
>>Spdy or HTTP/2 would allow.

Wouldn't Spdy or HTTP/2 still face the issues regarding steady-state then?

Part of my concern is that we may, once again, create an HTTP that
unfairly dominates traffic due to lots of bursty flows.

<snip>

>> I agree that solving the problem for http/2 alone won't fix it for
>>everything. On the other hand, we also need to act swiftly to solve
>>problems on timescales that matter to users, and http is a fine venue
>>for that. The fact that http/2 could do this doesn't stop us from coming
>>up with an opaque blob that *any* latency sensitive application protocol
>> could use to communicate with the transport layer.

As someone stated earlier, I fear the opposite to be true.  This may end
up slowing down HTTP/2 and not be swift at all..

Received on Tuesday, 16 April 2013 18:28:37 UTC