On Mon, Nov 26, 2012 at 4:10 PM, Oliver Neukum <[email protected]> wrote: > On Friday 23 November 2012 17:43:24 Dave Taht wrote: >> I was donated a raspberry pi in cambridge and got it booted today. >> It's a very cool >> box, an arm6, running debian, with hard floating point, and getting a >> complete >> development environment running, getting it to do mesh networking, >> graphics, apache, etc, on a 16GB SD card, was a breeze. >> >> But as for network performance: >> >> It only comes up at 100Mbit, and as noted elsewhere the ethernet chip >> is hooked up over USB. >> >> dmesg >> >> [3.078644] smsc95xx 1-1.1:1.0: eth0: register 'smsc95xx' at >> usb-bcm2708_usb-1.1, smsc95xx USB 2.0 Ethernet, b8:27:eb:18:fc:ac >> >> The best the 3.2 kernel based networking can do is about 75Mbit/sec. >> This eats 68% of cpu in the "system" (sy in top) and 30% in si (system >> interrupt) > > Wow. What did you do to saturate the system like this? Blow empty > UDP packages into the net?
A single TCP stream. I built netperf 2.6 with --enable-demo, ran netserver on it, and hit it with single netperf -l60 -H pi I don't remember if the performance I got from it was with -t TCP_STREAM or -t TCP_MAERTS (probably the latter). I will re-run the test with iperf, also, the next time I boot it. Other than this it's a pretty darn cool board, and if I had time I'd dream up a zillion projects for it... It does look rather easy to compile or cross compile kernels for it, too... > >> I had had some hope of this being a good box to put some test tools on, >> but with performance like this, I am back to leveraging the mips stuff. >> >> That said, I do intend to poke at the driver and update to 3.6 when >> I get a chance, since we have patches lying around for both this >> chip and the usbnet code. > > Nothing for performance in the mean time. Note that we don't try to > do interrupt mitigation in usbnet. ok. > Regards > Oliver > -- Dave Täht Fixing bufferbloat with cerowrt: http://www.teklibre.com/cerowrt/subscribe.html _______________________________________________ Cerowrt-devel mailing list [email protected] https://lists.bufferbloat.net/listinfo/cerowrt-devel
