NETMAP application architecture question

[Slawa Olhovchenkov]

On Fri, Sep 16, 2016 at 05:05:33PM +0200, Luigi Rizzo wrote:

> Hi,
> I don't think there is any hard limitation on the total number
> of pipes, very likely the number (64) is just some arbitrary
> limit that we set, and can be increased through a sysctl or
> worst case a compile time constant.

I am don't see sysctl for this.
Re-compile is not comfortable.

In any way, for this setup I am need to many resources, as I am calc:
buf_num=1114112
ring_num=964
if_num=248

This can introduce to high overhead.

> Please have a look at the source code if you can find where
> you are hitting the limit, and which parameters are involved.
> In case you don't find it, get back to us in a week (we are
> busy on a deadline at the moment).

OK

> Note that you should look at the netmap code on github, the one in
> the freebsd tree is not up to date.

Do you plan to update code in freebsd tree?

> Cheers
> Luigi
> 
> On Fri, Sep 16, 2016 at 4:57 PM, Slawa Olhovchenkov <slw at zxy.spb.ru> wrote:
> > I am wrote NETMAP application and meet some limitation.
> > I am use server 16-core server.
> > Workers thread run mostly independend, with minimal interworking.
> > I am use balancer threads for distributing packet flow between worker
> > threads.
> > I am using two NETMAP pipes between balancer and workers.
> > As result, for case of 4 balancer and 12 workers I am need 4x12x2 = 96
> > pipes. NETMAP have limitation of 64 pipes.
> >
> > May be exist more optimal way?
> >
> > May be I can emulate tilera way, with bufers credits?
> > (In this case balancer give RX buffers, confirm to kernel and pass it
> > to worker. kernel reduce credit, used for reciving other buffer from
> > pool. After complete worker pass buffer to balancer and balancer
> > return buffer to kernel, kernel rise credits and put free buffer to
> > pool).
> > In this case I am not need to many pipes and not limited performance
> > by too long processing of one packet.
> > _______________________________________________
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> 
> 
> 
> -- 
> -----------------------------------------+-------------------------------
>  Prof. Luigi RIZZO, rizzo at iet.unipi.it  . Dip. di Ing. dell'Informazione
>  http://www.iet.unipi.it/~luigi/        . Universita` di Pisa
>  TEL      +39-050-2217533               . via Diotisalvi 2
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