On Tue, Apr 17, 2018 at 3:09 PM, Bruce A. Mah <b...@es.net> wrote: > If memory serves me right, Jeffrey Lane wrote: >> Hi all, >> >> I have what is kind of a silly question, but who has some experience >> testing 100Gb with iperf3? >> >> I just wanted to validate something with iperf3 to see if it is reasonable. >> >> With a single process running, the most I've been able to get out of a >> 100Gb network port is a burst of about 65Gb/s with sustained averages >> of around 50-55Gb/s. >> >> This is after a LOT of kernel tweaks, PCIe tweaks, and network config tweaks. >> >> So at this point, I'm thinking that what I'm seeing is a hardware >> bottleneck, since iperf3 isn't multi-threaded. >> >> What I wanted to validate, to get around that is this: >> >> On the target side, I've kicked off four iperf3 processes all bound to >> the same IP but listening on a different port. Now, on the client >> side, I kick off four iperf3 instances, one per remote port. After 30 >> minutes of testing, each instance returns an average throughput of >> about 23Gb/s. >> >> So in that scenario is it reasonable that 4 parallel threads reporting >> 23Gb/s can be aggregated to assume we're actually seeing throughput of >> 92Gb/s on the 100Gb port (thus nearly saturated)? > > That all seems reasonable. We have some experience with iperf3 in very > high speed links, and yes, there's some amount of tuning that might be > involved. > > https://fasterdata.es.net/ has some information on tuning hardware and > software.
Thanks, I'll look into it. > Note that the reported throughput is application-level throughput > (payload only) and doesn't include protocol overheads. Yeah, I get that, which is why I don't expect to see numbers approaching 100% of theoretical limit, I assumed there was a loss for overhead somewhere. Glad to know my math adds up, though, many thanks everyone! > > Bruce. > > > > > -- Jeff Lane TPP / Server Certification Lead "Entropy isn't what it used to be." ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Iperf-users mailing list Iperf-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/iperf-users
