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Re: 923Mbits/s across the ocean
On Sun, Mar 09, 2003 at 02:25:25PM +0100, Iljitsch van Beijnum quacked: > > On Sat, 8 Mar 2003, Joe St Sauver wrote: > > > you will see that for bulk TCP flows, the median throughput is still only > > 2.3Mbps. 95th%-ile is only ~9Mbps. That's really not all that great, > > throughput wise, IMHO. > > Strange. Why is that? RFC 1323 is widely implemented, although not > widely enabled (and for good reason: the timestamp option kills header > compression so it's bad for lower-bandwidth connections). My guess is > that the OS can't afford to throw around MB+ size buffers for every TCP > session so the default buffers (which limit the windows that can be > used) are relatively small and application programmers don't override > the default. Which makes it doubly a shame that the adaptive buffer tuning tricks haven't made it into production systems yet. It was a beautiful, simple idea that worked very well for adapting to long fat networks: http://www.acm.org/sigcomm/sigcomm98/tp/abs_26.html -dave -- work: email@example.com me: firstname.lastname@example.org MIT Laboratory for Computer Science http://www.angio.net/ I do not accept unsolicited commercial email. Do not spam me.