netdev - Re: [PATCH net-next 1/2] xdp: Always use a devmap for XDP

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20190221161950.1938cc8c@carbon>
Date:   Thu, 21 Feb 2019 16:19:50 +0100
From:   Jesper Dangaard Brouer <brouer@...hat.com>
To:     Toke Høiland-Jørgensen <toke@...hat.com>
Cc:     David Miller <davem@...emloft.net>, netdev@...r.kernel.org,
        Daniel Borkmann <daniel@...earbox.net>,
        Alexei Starovoitov <ast@...nel.org>, brouer@...hat.com
Subject: Re: [PATCH net-next 1/2] xdp: Always use a devmap for XDP_REDIRECT
 to a device


You forgot at cover letter describing why we are doing this...
even-though is should be obvious from the performance results ;-)


On Thu, 21 Feb 2019 12:56:54 +0100 Toke Høiland-Jørgensen <toke@...hat.com> wrote:

> Before patch:
> xdp_redirect:     5426035 pkt/s
> xdp_redirect_map: 8412754 pkt/s
> 
> After patch:
> xdp_redirect:     8314702 pkt/s
> xdp_redirect_map: 8411854 pkt/s
> 
> This corresponds to a 53% increase in xdp_redirect performance, or a
> reduction in per-packet processing time by 64 nanoseconds.

(1/5426035-1/8314702)*10^9 = 64.0277 almost exactly 64 nanosec

(1/8412754-1/8411854)*10^9 = -0.012 => no regression for xdp_redirect_map

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