netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jesse Brandeburg <jesse.brandeburg@intel.com>
To: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: John Fastabend <john.fastabend@gmail.com>,
	David Miller <davem@davemloft.net>, <netdev@vger.kernel.org>,
	<andy@greyhouse.net>, <daniel@iogearbox.net>, <ast@fb.com>,
	<alexander.duyck@gmail.com>, <bjorn.topel@intel.com>,
	<jakub.kicinski@netronome.com>, <ecree@solarflare.com>,
	<sgoutham@cavium.com>, <Yuval.Mintz@cavium.com>,
	<saeedm@mellanox.com>, "Andi Kleen" <andi@firstfloor.org>
Subject: Re: [RFC PATCH 00/12] Implement XDP bpf_redirect vairants
Date: Mon, 17 Jul 2017 10:04:44 -0700	[thread overview]
Message-ID: <20170717100444.00007077@intel.com> (raw)
In-Reply-To: <20170716102308.163b9f91@redhat.com>

On Sun, 16 Jul 2017 10:23:08 +0200
Jesper Dangaard Brouer <brouer@redhat.com> wrote:

> On Tue, 11 Jul 2017 12:37:10 -0700 John Fastabend <john.fastabend@gmail.com> wrote:
> 
>  [...]  
> > 
> > hmm maybe Jesse or Alex have some clues. Adding them to the CC list.  
> 
> This seems related to Hyper-Threading.  I tried to disable
> hyperthreading in the BIOS, and the problem goes away.  That is, the
> benchmarks are no-longer affected by the CPU tuned-adm profile.

Wow, nice job figuring that out.  I went and took a look at tuned-adm
documentation but didn't see anything that stood out that would cause
the behavior you were seeing.

I suspect your toplev results showing this is a frontend problem mesh
nicely with the hyper-threading configuration inducing the bad behavior,
since there is still only one execution unit, and the fetchers would
have to stall.  I think you've rediscovered why the forwarding /
routing crowd generally turns off hyperthreading.

      reply	other threads:[~2017-07-17 17:04 UTC|newest]

Thread overview: 43+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-07-07 17:34 [RFC PATCH 00/12] Implement XDP bpf_redirect vairants John Fastabend
2017-07-07 17:34 ` [RFC PATCH 01/12] ixgbe: NULL xdp_tx rings on resource cleanup John Fastabend
2017-07-07 17:35 ` [RFC PATCH 02/12] net: xdp: support xdp generic on virtual devices John Fastabend
2017-07-07 17:35 ` [RFC PATCH 03/12] xdp: add bpf_redirect helper function John Fastabend
2017-07-09 13:37   ` Saeed Mahameed
2017-07-10 17:23     ` John Fastabend
2017-07-11 14:09       ` Andy Gospodarek
2017-07-11 18:38         ` John Fastabend
2017-07-11 19:38           ` Jesper Dangaard Brouer
2017-07-12 11:00             ` Saeed Mahameed
2017-07-07 17:35 ` [RFC PATCH 04/12] xdp: sample program for new bpf_redirect helper John Fastabend
2017-07-07 17:36 ` [RFC PATCH 05/12] net: implement XDP_REDIRECT for xdp generic John Fastabend
2017-07-07 17:36 ` [RFC PATCH 06/12] ixgbe: add initial support for xdp redirect John Fastabend
2017-07-07 17:36 ` [RFC PATCH 07/12] xdp: add trace event " John Fastabend
2017-07-07 17:37 ` [RFC PATCH 08/12] bpf: add devmap, a map for storing net device references John Fastabend
2017-07-08 18:57   ` Jesper Dangaard Brouer
2017-07-07 17:37 ` [RFC PATCH 09/12] bpf: add bpf_redirect_map helper routine John Fastabend
2017-07-07 17:37 ` [RFC PATCH 10/12] xdp: Add batching support to redirect map John Fastabend
2017-07-10 17:53   ` Jesper Dangaard Brouer
2017-07-10 17:56     ` John Fastabend
2017-07-07 17:38 ` [RFC PATCH 11/12] net: add notifier hooks for devmap bpf map John Fastabend
2017-07-07 17:38 ` [RFC PATCH 12/12] xdp: bpf redirect with map sample program John Fastabend
2017-07-07 17:48 ` [RFC PATCH 00/12] Implement XDP bpf_redirect vairants John Fastabend
2017-07-08  9:46   ` David Miller
2017-07-08 19:06     ` Jesper Dangaard Brouer
2017-07-10 18:30       ` Jesper Dangaard Brouer
2017-07-11  0:59         ` John Fastabend
2017-07-11 14:23           ` Jesper Dangaard Brouer
2017-07-11 18:26             ` John Fastabend
2017-07-13 11:14               ` Jesper Dangaard Brouer
2017-07-13 16:16                 ` Jesper Dangaard Brouer
2017-07-13 17:00                   ` John Fastabend
2017-07-13 18:21                     ` David Miller
2017-07-11 15:36       ` Jesper Dangaard Brouer
2017-07-11 17:48         ` John Fastabend
2017-07-11 18:01           ` Jesper Dangaard Brouer
2017-07-11 18:29             ` John Fastabend
2017-07-11 18:44             ` Jesper Dangaard Brouer
2017-07-11 18:56               ` John Fastabend
2017-07-11 19:19                 ` Jesper Dangaard Brouer
2017-07-11 19:37                   ` John Fastabend
2017-07-16  8:23                     ` Jesper Dangaard Brouer
2017-07-17 17:04                       ` Jesse Brandeburg [this message]

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=20170717100444.00007077@intel.com \
    --to=jesse.brandeburg@intel.com \
    --cc=Yuval.Mintz@cavium.com \
    --cc=alexander.duyck@gmail.com \
    --cc=andi@firstfloor.org \
    --cc=andy@greyhouse.net \
    --cc=ast@fb.com \
    --cc=bjorn.topel@intel.com \
    --cc=brouer@redhat.com \
    --cc=daniel@iogearbox.net \
    --cc=davem@davemloft.net \
    --cc=ecree@solarflare.com \
    --cc=jakub.kicinski@netronome.com \
    --cc=john.fastabend@gmail.com \
    --cc=netdev@vger.kernel.org \
    --cc=saeedm@mellanox.com \
    --cc=sgoutham@cavium.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).