> > Hi Ciara, > > Thank you for your quick response and useful tips. > That's a good idea to change the rx flow, I will test it later. > > Meanwhile, I tested AF_XDP PMD with 1rx/1tx queue configuration. The > performance is too worse than MLX5 PMD, nearly 2/3 drop... total traffic is > 3Gbps. > I also checked some statistics, it shows drops on xdp recv and app internel > transfer, it seems xdp recv and send take times, since there is no difference > on app side bettween the two tests(dpdk/xdp). > > Are there any extra configuration is required for AF_XDP PMD ? > The XDP PMD should have similar performance as DPDK PMD under 10Gbps > ?
Hi Christian, You're welcome. I have some suggestions for improving the performance. 1. Preferred busy polling If you are willing to upgrade your kernel to >=5.11 and your DPDK to v21.05 you can avail of the preferred busy polling feature. Info on the benefits can be found here: http://mails.dpdk.org/archives/dev/2021-March/201172.html Essentially it should improve the performance for a single core use case (driver and application on same core). 2. IRQ pinning If you are not using the preferred busy polling feature, I suggest pinning the IRQ for your driver to a dedicated core that is not busy with other tasks eg. the application. For most devices you can find IRQ info in /proc/interrupts and you can change the pinning by modifying /proc/irq/<irq_number>/smp_affinity 3. Queue configuration Make sure you are using all queues on the device. Check the output of ethtool -l <iface> and either set the PMD queue_count to equal the number of queues, or reduce the number of queues using ethtool -L <iface> combined N. I can't confirm whether the performance should reach that of the driver-specific PMD, but hopefully some of the above helps getting some of the way there. Thanks, Ciara > > Br, > Christian > ________________________________________ > 发件人: Loftus, Ciara <mailto:ciara.lof...@intel.com> > 发送时间: 2021年11月4日 10:19 > 收件人: Hong Christian <mailto:hongguoc...@hotmail.com> > 抄送: mailto:users@dpdk.org <mailto:users@dpdk.org>; > mailto:xiaolong...@intel.com <mailto:xiaolong...@intel.com> > 主题: RE: pmd_af_xdp: does net_af_xdp support different rx/tx queue > configuration > > > > > Hello DPDK users, > > > > Sorry to disturb. > > > > I am currently testing net_af_xdp device. > > But I found the device configure always failed if I configure my rx queue != > tx > > queue. > > In my project, I use pipeline mode, and require 1 rx and several tx queues. > > > > Example: > > I run my app with paramter: "--no-pci --vdev > > net_af_xdp0,iface=ens12,queue_count=2 --vdev > > net_af_xdp1,iface=ens13,queue_count=2" > > And config 1 rx and 2 tx queue, it will setup failed by print: "Port0 > > dev_configure = -22" > > > > After checking some xdp docs, I found the rx and tx always bind to use, > > which connected to filling and completing ring. > > But I still want to comfirm this with you ? Could you please share your > > comments ? > > Thanks in advance. > > Hi Christian, > > Thanks for your question. Yes, at the moment this configuration is forbidden > for the AF_XDP PMD. One socket is created for each pair of rx and tx queues. > However maybe this is an unnecessary restriction of the PMD. It is indeed > possible to create a socket with either one rxq or one txq. I will put looking > into the feasibility of enabling this in the PMD on my backlog. > In the meantime, one workaround you could try would be to create an even > number of rxq and txqs but steer all traffic to the first rxq using some NIC > filtering eg. tc. > > Thanks, > Ciara > > > > > Br, > > Christian
