On Wed, 22 Jan 2020, Christian Deacon wrote: > Hey everyone, > > I am new to XDP + AF_XDP (along with C programming in general), but I am very > interested in it and I've been learning a lot recently. I own an Anycast > network and our POP servers are running custom software our developer created > that processes packets using XDP. This software basically forwards specific > traffic to another machine via an IPIP tunnel. One issue I've been noticing is > the packets our software is processing and forwarding to another machine keep > dropping at higher traffic loads. I can't tell if this is dropping at the POP > level or if the machine the software is forwarding this specific traffic to > is. I've even tried upgrading the POP server from a two-core VPS (2.5 GHz > CPUs) to a dedicated server (Intel E3-1230v6 @ 3.5 GHz, 4 cores, and 8 > threads). If this is being dropped at the POP level, I'm wondering if the > software is being limited to one core on this specific POP (other POPs are > able to use more than one core specifically). However, I have no way to > confirm that. To my understanding XDP programs should be able to use more than > one core. > > My questions are the following: > > 1. Is there a way to see how much CPU the XDP program is using or the load of > the NIC? To my understanding, you cannot tell the XDP program's CPU usage > based off of something like `top` or `htop` due to that being in the user > space (XDP happens at the NIC driver level in the kernel IIRC). I am newbie in XDP too, maybe Linux Perf http://www.brendangregg.com/perf.html tool could help you figuring out which part of the code in your XDP app consuming CPU cycles (debug symbol needed)
|