On Wed, 2020-12-09 at 08:41 -0700, David Ahern wrote: > On 12/9/20 4:52 AM, Jesper Dangaard Brouer wrote: > > > > still load and either share queues across multiple cores or > > > > restirct > > > > down to a subset of CPUs. > > > > > > And that's the missing piece of logic, I suppose. > > > > > > > Do you need 192 cores for a 10gbps nic, probably not. > > > > > > Let's hear from Jesper :p > > > > LOL - of-cause you don't need 192 cores. With XDP I will claim > > that > > you only need 2 cores (with high GHz) to forward 10gbps wirespeed > > small > > packets. > > You don't need 192 for 10G on Rx. However, if you are using > XDP_REDIRECT > from VM tap devices the next device (presumably the host NIC) does > need > to be able to handle the redirect. > > My personal experience with this one is mlx5/ConnectX4-LX with a > limit This limit was removed from mlx5 https://patchwork.ozlabs.org/project/netdev/patch/20200107191335.12272-5-saeedm@xxxxxxxxxxxx/ Note: you still need to use ehttool to increase from 64 to 128 or 96 in your case. > of 63 queues and a server with 96 logical cpus. If the vhost thread > for > the tap device runs on a cpu that does not have an XDP TX Queue, the > packet is dropped. This is a really bizarre case to debug as some > packets go out fine while others are dropped. I agree, the user experience horrible.
