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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Best utilizing fat long pipes and large file transfer
> Date: Fri, 13 Jun 2008 12:40:48 -0400 > From: Robert Boyle <[email protected]> > > At 12:01 PM 6/13/2008, Kevin Oberman wrote: > >Clearly you have failed to try very hard or to check into what others > >have done. We routinely move data at MUCH higher rates over TCP at > >latencies over 50 ms. one way (>100 ms. RTT). We find it fairly easy to > >move data at over 4 Gbps continuously. > > That's impressive. > > >If you can't fill a GE to 80% (800 Mbps) at 30 ms, you really are not > >tying very hard. Note: I am talking about a single TCP stream running > >for over 5 minutes at a time on tuned systems. Tuning for most modern > >network stacks is pretty trivial. Some older stacks (e.g. FreeBSD V6) > >are hopeless. I can't speak to how Windows does as I make no use of it > >for high-speed bulk transfers. > > Let me refine my post then... > In our experience, you can't get to line speed with over 20-30ms of > latency using TCP on _Windows_ regardless of how much you tweak > it. >99% of the servers in our facilities are Windows based. I should > have been more specific. Sorry, but I don't do Windows, but my friends who do claim that this is not true. -- R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: [email protected] Phone: +1 510 486-8634 Key fingerprint:059B 2DDF 031C 9BA3 14A4 EADA 927D EBB3 987B 3751 Attachment:
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