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Date: Wed, 5 Jun 2013 09:28:00 -0500
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Subject: Re: netmap on wireless NIC
From: Chao Xu <caesarxuchao@gmail.com>
To: Luigi Rizzo <rizzo@iet.unipi.it>, adrian@freebsd.org,
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Thank you Adrian and Luigi. My goal is to reduce the latency, i.e. get the
packet as soon as it arrives on the NIC, and send the packet from user
space to NIC quickly. I think netmap will help because it skips the socket
layer and kernel network stack.


On Wed, Jun 5, 2013 at 8:45 AM, Luigi Rizzo <rizzo@iet.unipi.it> wrote:

> On Tue, Jun 04, 2013 at 04:06:35PM -0500, Chao Xu wrote:
> > Hello,
> >
> > Is it possible to hacking some wireless NIC driver (carl9170 for example)
> > to enable netmap on it? I guess this is possible because wireless drivers
> > also manage packets using ring buffers. My goal is to access the raw
> > packets as quickly as possible, not to achieve high data rate. Is there
> any
> > argument against doing so? Thank you.
>
> as other said, there is no negative argument but it does not
> seem worthwhile, because at least with current packet rates
> you should be able to extract packets using pcap.
> Unless, of course, you are running a 300Mbit/s interface
> on a slow embedded CPU, in which case the efficiency of
> netmap might be helpful.
>
> cheers
> luigi
>



-- 
Regards,
Chao Xu