irtt is used if available. I agree that the ping method is poor at lower scales. The ping volume also accounts for more bandwidth the lower the rtt which rrul does not measure. I would not mind trying to produce a rrul2021 test that updated it better for modern conditions.
On Mon, Mar 29, 2021 at 11:29 AM Aaron Wood <[email protected]> wrote: > > One of my long concerns with the RRUL test is that the ICMP ping test portion > is not isochronous, and runs at a variable rate based on rtt, which means > that it uses more/less bandwidth as an inverse function of rtt, and that > makes it harder to compare the actual goodput of the tcp streams running in > parallel. (When the top-line total bw goes down when latency goes down, > because the icmp and udp ping tests are using more bandwidth that isn’t > accounted for in the bw totals) > > On Sat, Mar 27, 2021 at 2:45 PM Dave Taht <[email protected]> wrote: >> >> most of the latency related portions of flent use irtt, which I think >> is a lot more solid than anything else. >> >> On Sat, Mar 27, 2021 at 2:44 PM Dave Taht <[email protected]> wrote: >> > >> > so glad to hear the license has been fixed. >> > >> > carl, iperf is only used in a few of flent's tests. We trusted netperf >> > - as did the linux kernel developers - a lot further than all the >> > iperf variants combined - at the time we started work on flent. >> > >> > I would not mind us somehow developing a drop in replacement for >> > netperf, perhaps leveraging the irtt codebase, as I have a long >> > standing desire to be able to reliably measure latencies and the >> > output of TCP_INFO in "some" tool below 250us. >> > >> > iperf has come a long way, but getting to where I could trust the >> > largely "academic" codebase it was would take a ton of benchmarking. >> > >> > On Sat, Mar 27, 2021 at 2:09 PM Klatsky, Carl via Bloat >> > <[email protected]> wrote: >> > > >> > > Toke, >> > > >> > > How you see this coming into Flent? My understanding is that for >> > > latency & load test like RRUL: >> > > >> > > -iperf provides the bandwidth portion >> > > -IRTT provides the latency portion, and if IRTT is not found, the test >> > > falls back to ICMP for the latency check >> > > >> > > Would netperf replace iperf for the bandwidth portion? Do you see it >> > > being used for the latency portion? >> > > >> > > Thanks, >> > > Carl >> > > >> > > -----Original Message----- >> > > From: Bloat <[email protected]> On Behalf Of Toke >> > > Høiland-Jørgensen via Bloat >> > > Sent: Friday, March 26, 2021 7:32 PM >> > > To: bloat <[email protected]> >> > > Subject: [Bloat] Netperf re-licensed as MIT >> > > >> > > Hopefully this means we can get it packaged for the distros that have >> > > thus far refused to because of the license - i.e., Debian and Fedora! >> > > >> > > -Toke >> > > _______________________________________________ >> > > Bloat mailing list >> > > [email protected] >> > > https://urldefense.com/v3/__https://lists.bufferbloat.net/listinfo/bloat__;!!CQl3mcHX2A!W_yWwnGSD6VuZvpn0BPv7Ta9GBP3f2dRWeJHPLS7RrrpBZ5gpyj5DZGnRYIfWVR5TXjR$ >> > > _______________________________________________ >> > > Bloat mailing list >> > > [email protected] >> > > https://lists.bufferbloat.net/listinfo/bloat >> > >> > >> > >> > -- >> > "For a successful technology, reality must take precedence over public >> > relations, for Mother Nature cannot be fooled" - Richard Feynman >> > >> > [email protected] <Dave Täht> CTO, TekLibre, LLC Tel: 1-831-435-0729 >> >> >> >> -- >> "For a successful technology, reality must take precedence over public >> relations, for Mother Nature cannot be fooled" - Richard Feynman >> >> [email protected] <Dave Täht> CTO, TekLibre, LLC Tel: 1-831-435-0729 >> _______________________________________________ >> Bloat mailing list >> [email protected] >> https://lists.bufferbloat.net/listinfo/bloat > > -- > - Sent from my iPhone. -- "For a successful technology, reality must take precedence over public relations, for Mother Nature cannot be fooled" - Richard Feynman [email protected] <Dave Täht> CTO, TekLibre, LLC Tel: 1-831-435-0729 _______________________________________________ Bloat mailing list [email protected] https://lists.bufferbloat.net/listinfo/bloat
