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From Dmitriy Lyubimov <dlie...@gmail.com>
Subject Re: 0.90 latency performance, cdh3b4
Date Fri, 22 Apr 2011 06:42:01 GMT
Exactly. that's why i said 'for short scans and gets' and perhaps a
combo. As soon as it exceeds a frame, we'd rather not to mess with
reassembly. But I agree it is most likely not worth it. Most likely
reason for my latencies is not this.

On Thu, Apr 21, 2011 at 11:22 PM, Ted Dunning <tdunning@maprtech.com> wrote:
> Yeah... but with UDP you have to do packet reassembly yourself.
>
> And do source quench and all kinds of things.
>
> Been there.  Done that.  Don't recommend it unless it is your day job.
>
> We built the Veoh peer to peer system on UDP.  It had compelling advantages
> for us as we moved a terabit of data per second 5 years ago, but it was
> distinctly non-trivial to get right.  The benefits we had included:
>
> - we could make our flows very aggressive, but less aggressive than TCP.
> That made them feel like smoke relative to web-surfing.  (not a benefit
> here)
>
> - we could handle thousands of connections if necessary (not a benefit here)
>
> - we could penetrate firewalls more easily by state spoofing (not a benefit
> here)
>
> - our protocol did magical window reassembly from multiple sources (not a
> benefit here)
>
> But getting this to work was weeks of work and months of testing with
> thousands of different clients.  I wouldn't want to repeat that without
> serious reasons.
>
>
> On Thu, Apr 21, 2011 at 11:12 PM, Dmitriy Lyubimov <dlieu.7@gmail.com>wrote:
>
>> > What do you see here D?
>>
>> I am not sure. I am not very good at understanding network frames. but
>> tcp kind of spends a lot of resources to ensure the flow. While udp
>> wouldn't bother with all that nonsense.
>>
>

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