Subject: Re: [PATCH bpf-next 0/6] xsk: exit NAPI loop when AF_XDP Rx ring is full

From: Jesper Dangaard Brouer <[email-masked]>
Date: Fri, 4 Sep 2020 16:27:51 +0200

On Fri,  4 Sep 2020 15:53:25 +0200
Björn Töpel <[email-masked]> wrote:

> On my machine the "one core scenario Rx drop" performance went from
> ~65Kpps to 21Mpps. In other words, from "not usable" to
> "usable". YMMV.

We have observed this kind of dropping off an edge before with softirq
(when userspace process runs on same RX-CPU), but I thought that Eric
Dumazet solved it in 4cd13c21b207 ("softirq: Let ksoftirqd do its job").

I wonder what makes AF_XDP different or if the problem have come back?

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer