On Tue, Sep 20, 2016 at 3:03 PM, Dave Täht wrote: > Groovy. I note that I am really fond of the linux "fdtimer" notion for > tickers, we use that throughout the high speed stats gathering code in > flent. > > I'd really like a voip or ping tool that used those, and I've always > worried about iperf's internal notion of a sampling interval. > > On 9/20/16 3:00 PM, Aaron Wood wrote: > > I modified iperf3 to use a 1ms timer, and was able to get things much > > smoother. I doubt it's as smooth as iperf3 gets on Linux when fq pacing > > is used, but it's a big improvement vs. the nice small buffers in > switches. > Thanks! For rates of <1000 packets per second, the 1ms timer I put in will give something like that (it fires every ms, but that's just a check for sending or not). If you want to use it to model a 120pps flow of 64-byte packets: iperf3 -c -u -l 64 -b 61440 And then it will pace those out at roughly every 80ms (just verified this on my box) -Aaron