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From: David Miller <davem@davemloft.net>
To: therbert@google.com
Cc: victor@inliniac.net, netdev@vger.kernel.org, willemb@google.com
Subject: Re: [PATCH 0/2] AF_PACKET fanout support
Date: Tue, 05 Jul 2011 20:19:50 -0700 (PDT)	[thread overview]
Message-ID: <20110705.201950.199250194399828543.davem@davemloft.net> (raw)
In-Reply-To: <CA+mtBx8www2eNp38EDuagYMQGSYivG7SN4ffozz4QtZPZqubSQ@mail.gmail.com>

From: Tom Herbert <therbert@google.com>
Date: Tue, 5 Jul 2011 20:13:27 -0700

>>> Also, another useful mode of steering would be to steer packets to a
>>> socket which was recently processed by a thread running on the same
>>> CPU; somewhat analogous to RFS (cc'ed WIllem Bruijn who is already
>>> working on this I believe).
>>
>> This sounds like a good way to overload a local socket and prevent
>> pushing the work to lesser used sockets on other cpus.
>>
> Sure, it you're not using RPS or RSS!  These should already be
> distributing the RX work amongst CPUs.

One idea I did have while working on the PACKET_FANOUT bits was
to allow a packet socket to be bound to a particular cpu.  And
to implement this we'd have a per-cpu list of packet_type taps.

But in order for the user to make sure he gets all the traffic,
he'd have to make sure he bound one AF_PACKET socket to every
online cpu and then listened for all cpu hotplug events.

It doesn't really work.

  reply	other threads:[~2011-07-06  3:20 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-07-05  4:20 [PATCH 0/2] AF_PACKET fanout support David Miller
2011-07-06  0:46 ` Tom Herbert
2011-07-06  1:20   ` David Miller
2011-07-06  3:13     ` Tom Herbert
2011-07-06  3:19       ` David Miller [this message]
2011-07-06  4:07         ` Eric Dumazet
2011-07-06  6:44           ` David Miller
2011-07-06  6:55             ` David Miller

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