Andrew Gallatin wrote: > > Andre Oppermann writes: > > I've totally rewritten the TCP reassembly function to be a lot more > > efficient. In tests with normal bw*delay products and packet loss > > plus severe reordering I've measured an improvment of at least 30% in > > performance. For high and very high bw*delay product links the > > performance improvement is most likely much higher. > > > > I ran netperf with 20 times for each of 3 socket buffer sizes (128KB, > 256KB, and 1MB) before and after patching. All tests were run with > net.isr.enable=1, and machdep.cpu_idle_hlt=0. CPU was pretty much > maxed thoughout. (SMP kernel, 1 HTT p4).
HTT is not really good with FreeBSD's schedulers. Most of the time it hurts performance more than it helps. > I'm not sure how much weight you should give these result. I still > haven't gotten around to fixing kttcp, so the memory copy overhead is > pretty high. For xmit, b/w goes from 2.90Gb/sec to 3.95Gb/sec when > sendfile is used. (linux receiver on same hw). Ok. > I've also not gotten around to making any of Robert's suggested driver > optimizations. Ok. > I noticed that at least systat was not printing the number of tcp > out-of-order packets after applying the patch. I forgot to check > netstat itself. Duh, that's missing in the patch. Good you noticed. Regarding your measurements, did you measure the bandwidth as reported by Netperf? Is a FreeBSD box on both sides (you mentioned Linux)? -- Andre > Drew > > x before.131072 > + after.131072 > +--------------------------------------------------------------------------+ > | ++ x + x x| > |+ *+ + + ++ +xx++ x +x* ++ + xx+x x x + x x xxxx| > | |_____________AM|___________|_______AM__________________| | > +--------------------------------------------------------------------------+ > N Min Max Median Avg Stddev > x 20 3336.63 3516.95 3449.87 3447.838 52.708815 > + 20 3323 3466.34 3391.97 3389.686 37.154513 > Difference at 95.0% confidence > -58.152 +/- 29.1859 > -1.68662% +/- 0.846499% > (Student's t, pooled s = 45.5998) > > x before.262144 > + after.262144 > +--------------------------------------------------------------------------+ > | + | > | + x | > |+ ++ + ++ x x x | > |+ + ++++++++ + + x x x x x xx xxx xxxx x x| > | |______A______| |_______AM_______| | > +--------------------------------------------------------------------------+ > N Min Max Median Avg Stddev > x 20 3197.77 3421.67 3316.64 3314.8555 59.787371 > + 20 2889.64 3122.17 2965.01 2964.9865 50.076867 > Difference at 95.0% confidence > -349.869 +/- 35.2961 > -10.5546% +/- 1.06479% > (Student's t, pooled s = 55.1463) > > x before.1048576 > + after.1048576 > +--------------------------------------------------------------------------+ > | x + | > |xx x + x xx + x+x++x * x* x+*x+x+* x*+ + + + ++| > | |_________________|A____M__________A__M____________| | > +--------------------------------------------------------------------------+ > N Min Max Median Avg Stddev > x 20 2658.05 2732.45 2706.91 2700.1955 23.318833 > + 20 2676.13 2748.97 2724.07 2719.9665 20.531036 > Difference at 95.0% confidence > 19.771 +/- 14.0613 > 0.732206% +/- 0.52075% > (Student's t, pooled s = 21.9692) _______________________________________________ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "[EMAIL PROTECTED]"
