Which version of Pktgen? I just pushed a patch in 3.5.3 to fix a performance problem.
> On Aug 28, 2018, at 12:05 PM, Saber Rezvani <irsa...@zoho.com> wrote: > > > > On 08/28/2018 08:31 PM, Stephen Hemminger wrote: >> On Tue, 28 Aug 2018 17:34:27 +0430 >> Saber Rezvani <irsa...@zoho.com> wrote: >> >>> Hi, >>> >>> >>> I have run multi_process/symmetric_mp example in DPDK example directory. >>> For a one process its throughput is line rate but as I increase the >>> number of cores I see decrease in throughput. For example, If the number >>> of queues set to 4 and each queue assigns to a single core, then the >>> throughput will be something about 9.4. if 8 queues, then throughput >>> will be 8.5. >>> >>> I have read the following, but it was not convincing. >>> >>> http://mails.dpdk.org/archives/dev/2015-October/024960.html >>> >>> >>> I am eagerly looking forward to hearing from you, all. >>> >>> >>> Best wishes, >>> >>> Saber >>> >>> >> Not completely surprising. If you have more cores than packet line rate >> then the number of packets returned for each call to rx_burst will be less. >> With large number of cores, most of the time will be spent doing reads of >> PCI registers for no packets! > Indeed pktgen says it is generating traffic at line rate, but receiving less > than 10 Gb/s. So, it that case there should be something that causes the > reduction in throughput :( > > Regards, Keith
