From: "Toke Høiland-Jørgensen" <toke@redhat.com>
To: Sridhar Samudrala <sridhar.samudrala@intel.com>,
magnus.karlsson@intel.com, bjorn.topel@intel.com,
netdev@vger.kernel.org, bpf@vger.kernel.org,
sridhar.samudrala@intel.com, intel-wired-lan@lists.osuosl.org,
maciej.fijalkowski@intel.com, tom.herbert@intel.com
Subject: Re: [PATCH bpf-next 0/5] Add support for SKIP_BPF flag for AF_XDP sockets
Date: Thu, 15 Aug 2019 13:12:37 +0200 [thread overview]
Message-ID: <87ftm2adi2.fsf@toke.dk> (raw)
In-Reply-To: <1565840783-8269-1-git-send-email-sridhar.samudrala@intel.com>
Sridhar Samudrala <sridhar.samudrala@intel.com> writes:
> This patch series introduces XDP_SKIP_BPF flag that can be specified
> during the bind() call of an AF_XDP socket to skip calling the BPF
> program in the receive path and pass the buffer directly to the socket.
>
> When a single AF_XDP socket is associated with a queue and a HW
> filter is used to redirect the packets and the app is interested in
> receiving all the packets on that queue, we don't need an additional
> BPF program to do further filtering or lookup/redirect to a socket.
>
> Here are some performance numbers collected on
> - 2 socket 28 core Intel(R) Xeon(R) Platinum 8180 CPU @ 2.50GHz
> - Intel 40Gb Ethernet NIC (i40e)
>
> All tests use 2 cores and the results are in Mpps.
>
> turbo on (default)
> ---------------------------------------------
> no-skip-bpf skip-bpf
> ---------------------------------------------
> rxdrop zerocopy 21.9 38.5
> l2fwd zerocopy 17.0 20.5
> rxdrop copy 11.1 13.3
> l2fwd copy 1.9 2.0
>
> no turbo : echo 1 > /sys/devices/system/cpu/intel_pstate/no_turbo
> ---------------------------------------------
> no-skip-bpf skip-bpf
> ---------------------------------------------
> rxdrop zerocopy 15.4 29.0
> l2fwd zerocopy 11.8 18.2
> rxdrop copy 8.2 10.5
> l2fwd copy 1.7 1.7
> ---------------------------------------------
You're getting this performance boost by adding more code in the fast
path for every XDP program; so what's the performance impact of that for
cases where we do run an eBPF program?
Also, this is basically a special-casing of a particular deployment
scenario. Without a way to control RX queue assignment and traffic
steering, you're basically hard-coding a particular app's takeover of
the network interface; I'm not sure that is such a good idea...
-Toke
next prev parent reply other threads:[~2019-08-15 11:12 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-15 3:46 [PATCH bpf-next 0/5] Add support for SKIP_BPF flag for AF_XDP sockets Sridhar Samudrala
2019-08-15 3:46 ` [PATCH bpf-next 1/5] xsk: Convert bool 'zc' field in struct xdp_umem to a u32 bitmap Sridhar Samudrala
2019-08-15 3:46 ` [PATCH bpf-next 2/5] xsk: Introduce XDP_SKIP_BPF bind option Sridhar Samudrala
2019-08-15 3:46 ` [PATCH bpf-next 3/5] i40e: Enable XDP_SKIP_BPF option for AF_XDP sockets Sridhar Samudrala
2019-08-16 9:21 ` kbuild test robot
2019-08-15 3:46 ` [PATCH bpf-next 4/5] ixgbe: " Sridhar Samudrala
2019-08-15 3:46 ` [PATCH bpf-next 5/5] xdpsock_user: Add skip_bpf option Sridhar Samudrala
2019-08-15 11:12 ` Toke Høiland-Jørgensen [this message]
2019-08-15 16:25 ` [PATCH bpf-next 0/5] Add support for SKIP_BPF flag for AF_XDP sockets Samudrala, Sridhar
2019-08-15 17:11 ` Toke Høiland-Jørgensen
2019-08-16 6:12 ` Samudrala, Sridhar
2019-08-15 12:51 ` Björn Töpel
2019-08-15 16:46 ` Samudrala, Sridhar
2019-08-16 13:32 ` [Intel-wired-lan] " Björn Töpel
2019-08-16 22:08 ` Jonathan Lemon
2019-08-19 7:39 ` Björn Töpel
2019-08-15 19:28 ` Jakub Kicinski
2019-08-16 6:25 ` Samudrala, Sridhar
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87ftm2adi2.fsf@toke.dk \
--to=toke@redhat.com \
--cc=bjorn.topel@intel.com \
--cc=bpf@vger.kernel.org \
--cc=intel-wired-lan@lists.osuosl.org \
--cc=maciej.fijalkowski@intel.com \
--cc=magnus.karlsson@intel.com \
--cc=netdev@vger.kernel.org \
--cc=sridhar.samudrala@intel.com \
--cc=tom.herbert@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).