From: Tom Herbert <therbert@google.com>
To: Ben Hutchings <bhutchings@solarflare.com>
Cc: Zhi Yong Wu <zwu.kernel@gmail.com>,
Stefan Hajnoczi <stefanha@redhat.com>,
Linux Netdev List <netdev@vger.kernel.org>,
Eric Dumazet <edumazet@google.com>,
"David S. Miller" <davem@davemloft.net>,
Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Subject: Re: [RFC PATCH net-next 3/3] virtio-net: Add accelerated RFS support
Date: Fri, 17 Jan 2014 20:59:15 -0800 [thread overview]
Message-ID: <CA+mtBx8eRuWpYkYoPbuCaO1h0Y+g96zJB96zP17ZixOwZ1_gmQ@mail.gmail.com> (raw)
In-Reply-To: <1389979208.27141.11.camel@bwh-desktop.uk.level5networks.com>
Ben,
I've never quite understood why flow management in aRFS has to be done
with separate messages, and if I recall this seems to mitigate
performance gains to a large extent. It seems like we should be able
to piggyback on a TX descriptor for a connection information about the
RX side for that connection, namely the rxhash and queue mapping.
State creation should be implicit by just seeing a new rxhash value,
tear down might be accomplished with a separate flag on the final TX
packet on the connection (this would need some additional logic in the
stack). Is this method not feasible in either NICs or virtio-net?
On Fri, Jan 17, 2014 at 9:20 AM, Ben Hutchings
<bhutchings@solarflare.com> wrote:
> On Sat, 2014-01-18 at 00:54 +0800, Zhi Yong Wu wrote:
>> On Fri, Jan 17, 2014 at 7:16 AM, Ben Hutchings
>> <bhutchings@solarflare.com> wrote:
> [...]
>> > However, to take advantage of ARFS on a physical net driver, it would be
>> > necessary to send a control request for part 2.
>> aRFS on a physical net driver? What is this physical net driver? I
>> thought that in order to enable aRFS, guest virtio_net driver should
>> send a control request to its emulated virtio_net NIC.
> [...]
>
> If the backend is connected to a macvlan device on top of a physical net
> device that supports ARFS, then there is further potential for improving
> performance by steering to the best physical RX queue and CPU as well as
> the best virtio_net RX queue and vCPU.
>
> Ben.
>
> --
> Ben Hutchings, Staff Engineer, Solarflare
> Not speaking for my employer; that's the marketing department's job.
> They asked us to note that Solarflare product names are trademarked.
>
next prev parent reply other threads:[~2014-01-18 4:59 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-01-15 14:20 [RFC PATCH net-next 0/3] virtio_net: add aRFS support Zhi Yong Wu
2014-01-15 14:20 ` [RFC PATCH net-next 1/3] virtio_pci: Introduce one new config api vp_get_vq_irq() Zhi Yong Wu
2014-01-15 14:20 ` [RFC PATCH net-next 2/3] virtio_net: Introduce one dummy function virtnet_filter_rfs() Zhi Yong Wu
2014-01-15 17:54 ` Tom Herbert
2014-01-16 2:45 ` Zhi Yong Wu
2014-01-15 14:20 ` [RFC PATCH net-next 3/3] virtio-net: Add accelerated RFS support Zhi Yong Wu
2014-01-16 21:31 ` Ben Hutchings
2014-01-16 22:00 ` Zhi Yong Wu
2014-01-16 23:16 ` Ben Hutchings
2014-01-17 16:54 ` Zhi Yong Wu
2014-01-17 17:20 ` Ben Hutchings
2014-01-18 4:59 ` Tom Herbert [this message]
2014-01-18 14:19 ` Ben Hutchings
2014-01-16 4:23 ` [RFC PATCH net-next 0/3] virtio_net: add aRFS support Jason Wang
2014-01-16 8:34 ` Fwd: " Zhi Yong Wu
2014-01-16 8:52 ` Stefan Hajnoczi
2014-01-16 17:12 ` Tom Herbert
2014-01-17 3:26 ` Jason Wang
2014-01-17 5:08 ` Tom Herbert
2014-01-17 6:36 ` Jason Wang
2014-01-17 16:03 ` Tom Herbert
2014-01-17 5:22 ` Stefan Hajnoczi
2014-01-17 6:45 ` Jason Wang
2014-01-20 14:36 ` Ben Hutchings
2014-01-22 13:27 ` Zhi Yong Wu
2014-01-22 18:00 ` Tom Herbert
2014-01-23 0:40 ` Zhi Yong Wu
2014-01-23 14:23 ` Michael S. Tsirkin
2014-01-17 3:04 ` Jason Wang
2014-01-20 16:49 ` Stefan Hajnoczi
2014-01-16 8:48 ` Zhi Yong Wu
2014-01-23 14:26 ` Michael S. Tsirkin
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