From mboxrd@z Thu Jan  1 00:00:00 1970
From: Robert Olsson <robert@herjulf.net>
Subject: Re: [PATCH net-2.6] Re: rib_trie / Fix inflate_threshold_root.
	Now=15 size=11 bits
Date: Thu, 2 Jul 2009 17:31:58 +0200
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Cc: =?iso-8859-2?Q?Pawe=B3?= Staszewski <pstaszewski@itcare.pl>,
	Linux Network Development list <netdev@vger.kernel.org>,
	Robert Olsson <Robert.Olsson@data.slu.se>
To: Jarek Poplawski <jarkao2@gmail.com>
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Jarek Poplawski writes:

 > Yes, it looks like we can't free memory so simple because of such huge
 > latencies.  

 Controlling RCU seems crucial. Insertion of the full BGP table increased
 from 2 seconds to > 20 min with one synchronize_rcu patches.

 And fib_trie "worst case" wrt memory is the root node. So maybe we should 
 monitor changes in root node and use this to control synchronize_rcu.

 Didn't Paul suggest something like this?

 And with don't find any decent solution we have to add an option for 
 a fixed and pre-allocated root-nod typically for BGP-routers.

 Cheers
					--ro