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Date: Sat, 19 Mar 2011 16:04:00 +0100
From: Alexander Leidinger <Alexander@Leidinger.net>
To: George Neville-Neil <gnn@neville-neil.com>
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Cc: arch@freebsd.org
Subject: Re: Updating our TCP and socket sysctl values...
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On Sat, 19 Mar 2011 15:37:47 +0900 George Neville-Neil
<gnn@neville-neil.com> wrote:

> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
> 
> Howdy,
> 
> I believe it's time for us to upgrade our sysctl values for TCP
> sockets so that they are more in line with the modern world.  At the
> moment we have these limits on our buffering:
> 
> kern.ipc.maxsockbuf: 262144
> net.inet.tcp.recvbuf_max: 262144
> net.inet.tcp.sendbuf_max: 262144
> 
> I believe it's time to up these values to something that's in line
> with higher speed local networks, such as 10G.  Perhaps it's time to
> move these to 2MB instead of 256K.
> 
> Thoughts?

I suggest to read
  http://www.bufferbloat.net/projects/bloat/wiki/Bufferbloat
and do a before/after test to make sure we do not suffer from the
described problem. Jim Getty has test descriptions:
  http://gettys.wordpress.com/category/bufferbloat/

Bye,
Alexander.