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Date: Mon, 15 Jul 2013 12:31:59 -0700
From: trafdev <trafdev@mail.ru>
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To: Sepherosa Ziehau <sepherosa@gmail.com>
Subject: Re: SO_REUSEPORT: strange kernel balancer behaviour
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Thanks for reply.

This approach produces lot of "resource temporary unavailable" (eagain) 
on accept-ing connections in N-1 processes.
Is this possible to avoid this by e.g. tweaking kqueue?

On Sun Jul 14 19:37:59 2013, Sepherosa Ziehau wrote:
> On Sat, Jul 13, 2013 at 1:16 PM, trafdev <trafdev@mail.ru> wrote:
>> Hello.
>>
>> Could someone help with following problem of SO_REUSEPORT.
>
> The most portable "load balance" between processes listening on the
> same TCP addr/port probably is:
>
> s=socket();
> bind(s);
> listen(s);
> /* various socketopt and fcntl as you needed */
> pid=fork();
> if (pid==0) {
>      server_loop(s);
>      exit(1);
> }
> server_loop(s);
> exit(1);
>
> Even in Linux or DragonFly SO_REUSEPORT "load balance" between
> processes listening on the same TCP addr/port was introduced recently,
> so you probably won't want to rely on it.
>
> Best Regards,
> sephe
>