Hi, i´ve also an APU2 as router. The uplink connection (16Mbit/s) is via pppoe(4) on em0 and i couldn´t manage to messure the throughput of this interface: - iftop doesn´t work on pppoe and shows nothing on em0. - ifperf also calculates some strange numbers (14669317741 Gbits/sec) when trying to connect to one of the public iperf-servers from https://iperf.fr/iperf-servers.php
how do you messure the performance? 2017-11-04 18:24 GMT+01:00 Peter Faiman <peterfai...@gmail.com>: > > On Nov 4, 2017, at 09:53, Chris Cappuccio <ch...@nmedia.net> wrote: > > > > Rupert Gallagher [r...@protonmail.com] wrote: > >> > >> You seem to say that handling larger packets is a feature of having > limited CPU. I disagree. > >> > > > > Rupert, I'm saying that a slower CPU can process less packets per second. > > > > The important measurement is packets-per-second. The APU has plenty of > > memory bandwidth to handle large volumes of data. For adequate CPU power, > > you have to either lower the cost of processing (make software > better/more > > efficient) or you have to distribute the cost across the 4 cores of the > APU2 > > (make software execution parallel). > > > >>> The same traffic level, with 1500 byte packets generates 6 times more > packets per second than that traffic level with 9000 bytes packets. > >> > >> You divided 9000 by 1500 without mistakes. Congratulations. > >> > > > > The point was clearly lost on you. > > > >>> There is ongoing work to improve the network stack performance on > boxes like the APU2 (which have 4 cores). You will see improvements. If you > want it better today, you need a faster box. Chris > >> > >> The apu2c4 is fast enough to saturate its Intel 1Gbits/sec link. It has > three of those. If you connect all three to the switch, you get 3Gbps shy. > No need for a faster box. You rather need a faster switch, class 7 S-FTP > wires (better than class 6), and 2.5Gbps lan cards for clients. > > > > No, you don't need any of that. You have no idea what you are talking > about. > > > > The APU requires software crafted to evenly distribute PER-PACKET > PROCESSING > > cost across multiple cores. That is what is happening in OpenBSD today. > It has > > been happening for years, and it is getting closer to becoming a reality > with > > OpenBSD + APU2, as well as other chipsets/platforms. > > > > For a couple years now, we've had interrupts processed by one core, PF on > > another, and other parts of the kernel on a third core. But to accelerate > > packet processing alone, we need interrupts handled on multiple cores, > > PF processing handled on multiple cores. This is hard work. > > > > By the way, what I'm describing is the general-purpose OS approach towads > > this problem. If you want to turn computer hardware into routers with > little > > other concern, the go-to platform is DPDK + VPP. It is something like an > > order of magnitude faster than any general purpose OS (OpenBSD, Linux) at > > packet pushing. > > > > https://www.reddit.com/r/networking/comments/6upchy/ > can_a_bsd_system_replicate_the_performance_of/dlvdq2e/ > > > > Chris > > Thank you for this explanation. My uplink is only 240mbit and my APU2 > handles that perfectly, so I’m not having any of these problems. But the > insight into the current state of networking was great! :) > > Peter > -- +49.179.1448024 Karl-Kunger-Straße 68 D - 12435 Berlin
