From mboxrd@z Thu Jan  1 00:00:00 1970
From: "David S. Miller" <davem@redhat.com>
Subject: Re: [RFC] Use RCU for fib_rules
Date: Wed, 31 Mar 2004 13:11:07 -0800
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To: Stephen Hemminger <shemminger@osdl.org>
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On Wed, 31 Mar 2004 13:05:41 -0800
Stephen Hemminger <shemminger@osdl.org> wrote:

> No, don't have enough rules or load in this area to cause an impact.
> But also, I don't have the test environment to really stress this
> (ie 1000's of rules).

You really don't need 1000's of rules.  Every time the routing cache
misses, it's going to dive into this code, so on SMP that would show up.

You could use stream.c (http://www.securiteam.com/unixfocus/5YP0I000DG.html)
as the DoS workload in order to thrash the routing cache and force the
rule codepath.