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Date: Sat, 20 Aug 2005 19:29:57 +0200
From: Andre Oppermann <andre@freebsd.org>
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To: Christian Vogt <chvogt@tm.uka.de>
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Cc: freebsd-net@freebsd.org, TM-RO2 <tm-ro2@tm.uka.de>
Subject: Re: Deactivate TCP Hostcache?
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Christian Vogt wrote:
> 
> Hi everybody,
> 
> is there a way to deactivate the TCP hostcache?
> 
> I could modify the kernel, but probably there is a more convenient way
> to do this.

No, there is no other way.

> The reason I want to deactivate the hostcache is because I am doing
> experiments and later measurements should not be different than earlier
> ones due to cached information.

Comment out the tcp_hc_update() call on line 737 in netinet/tcp_subr.c
and it won't cache metrics anymore.  The discovered path MTU is still
stored though.

-- 
Andre