On 05/15/2018 12:31 PM, Flavio Leitner wrote: > Hi, > > There is a significant throughput issue (~50% drop) for a single TCP > stream when the skb is scrubbed and XPS is enabled. > > If I turn CONFIG_XPS off, then the issue never happens and the test > reaches line rate. The same happens if I echo 0 to tx-*/xps_cpus. > > It looks like that when the skb is scrubbed, there is no more reference > to the struct sock,
And this is really the problem here, since it breaks back pressure (and TCP Small queues) I am not sure why skb_orphan() is used in this scrubbing really.
