On 02/08/2017 18:10, Måns Rullgård wrote: > Mason writes: > >> On 02/08/2017 17:56, Måns Rullgård wrote: >> >>> What does the tango5 do if you flood it with packets faster than the >>> kernel can keep up with? That would make it hit the end of the rx >>> chain, which is apparently what makes it miserable with the current dma >>> stop code. >> >> The simplest way to test this would be sending tiny packets >> as fast as possible, right? So ping -f on a GigE link should >> fit the bill? > > ping -f is limited to 100 packets per second. Use something like iperf > in UDP mode instead.
ping -f can go 100 times faster than 100 pps: # ping -f -q -c 150000 -s 300 172.27.64.45 PING 172.27.64.45 (172.27.64.45) 300(328) bytes of data. --- 172.27.64.45 ping statistics --- 150000 packets transmitted, 150000 received, 0% packet loss, time 15035ms rtt min/avg/max/mdev = 0.065/0.084/0.537/0.014 ms, ipg/ewma 0.100/0.087 ms 150,000 packets in 15 seconds = 10,000 pps (172.27.64.45 is the tango5 board) Ergo, dealing with 10,000 packets per second does not hose RX. Regards.
