netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Jason Wang <jasowang@redhat.com>
Cc: linux-kernel@vger.kernel.org,
	Eric Dumazet <eric.dumazet@gmail.com>,
	davem@davemloft.net, netdev@vger.kernel.org,
	Steven Rostedt <rostedt@goodmis.org>,
	brouer@redhat.com
Subject: Re: [PATCH v5 0/2] skb_array: array based FIFO for skbs
Date: Mon, 30 May 2016 18:37:05 +0300	[thread overview]
Message-ID: <20160530183455-mutt-send-email-mst@redhat.com> (raw)
In-Reply-To: <574C0F05.1040500@redhat.com>

On Mon, May 30, 2016 at 05:59:33PM +0800, Jason Wang wrote:
> 
> 
> On 2016年05月23日 18:43, Michael S. Tsirkin wrote:
> >This is in response to the proposal by Jason to make tun
> >rx packet queue lockless using a circular buffer.
> >My testing seems to show that at least for the common usecase
> >in networking, which isn't lockless, circular buffer
> >with indices does not perform that well, because
> >each index access causes a cache line to bounce between
> >CPUs, and index access causes stalls due to the dependency.
> 
> I change tun to use skb array, looks like it can give about 5% more faster
> than skb ring.

OK and skb ring is 9% faster than the linked list, so together
this is a 14% speedup?

> And we usually don't need touch bhs during consume and produce (e.g for the
> case of tun).
> 
> Thanks

Maybe I'll drop it in v6 then ...
Could you post the full tun patchset please?

-- 
MST

  reply	other threads:[~2016-05-30 15:37 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-05-23 10:43 [PATCH v5 0/2] skb_array: array based FIFO for skbs Michael S. Tsirkin
2016-05-23 10:43 ` [PATCH v5 1/2] " Michael S. Tsirkin
2016-05-23 10:43 ` [PATCH v5 2/2] skb_array: ring test Michael S. Tsirkin
2016-05-23 13:09   ` Jesper Dangaard Brouer
2016-05-23 20:52     ` Michael S. Tsirkin
2016-05-24 10:28       ` Jesper Dangaard Brouer
2016-05-24 10:33         ` Michael S. Tsirkin
2016-05-24 11:54         ` Michael S. Tsirkin
2016-05-24 12:11         ` Michael S. Tsirkin
2016-05-24 17:03         ` Jesper Dangaard Brouer
2016-05-24 20:34           ` Michael S. Tsirkin
2016-06-02 18:47             ` Jesper Dangaard Brouer
2016-06-03 12:15               ` Jesper Dangaard Brouer
2016-05-23 13:31 ` [PATCH v5 0/2] skb_array: array based FIFO for skbs Eric Dumazet
2016-05-23 20:35   ` Michael S. Tsirkin
2016-05-30  9:59 ` Jason Wang
2016-05-30 15:37   ` Michael S. Tsirkin [this message]
2016-05-31  2:29     ` Jason Wang

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=20160530183455-mutt-send-email-mst@redhat.com \
    --to=mst@redhat.com \
    --cc=brouer@redhat.com \
    --cc=davem@davemloft.net \
    --cc=eric.dumazet@gmail.com \
    --cc=jasowang@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=rostedt@goodmis.org \
    /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).