From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [RFC PATCH 0/4] inet: add second hash table
Date: Wed, 30 May 2012 14:41:02 +0200
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Cc: Alexandru Copot <alex.mihai.c@gmail.com>, davem@davemloft.net,
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To: Daniel Baluta <dbaluta@ixiacom.com>
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On Wed, 2012-05-30 at 15:32 +0300, Daniel Baluta wrote:


> Hi Eric,
> 
> Usually our tests use a huge number of virtual interfaces.
> Using this patch we get a massive improvement when there are many sockets
> bound to the same port, but different addresses for both bind() and
> listen() system calls (both call inet_csk_get_port).
> 	
> We provided some data points in the fourth patch:
> 
> For 16.000 interfaces each with a distinct IPv4 address, doing bind
> and then listen we get:
> 

> 
> If I understood it correctly, a similar patch was introduced
> for UDP some time ago. [2]
> 
> thanks,
> Daniel.
> 
> [1] http://ixlabs.cs.pub.ro/gitweb/?p=port-allocation.git;a=tree;f=testbind;h=687e4452101e13cb5995b43c1351d76786d98fdd;hb=HEAD
> [2] http://www.spinics.net/lists/netdev/msg112056.html


UDP case was a bit different, since production machine could really have
thousand of UDP flows for tunnel terminations.

But for TCP, unless your very specific needs I don't see the real need
to review 400 lines of patches ?

Nobody but you ever complained of listen() being performance critical
with 16.000 IP on a machime...