From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: Linux Route Cache performance tests
Date: Mon, 07 Nov 2011 10:08:42 +0100
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To: =?UTF-8?Q?Pawe=C5=82?= Staszewski <pstaszewski@itcare.pl>
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Le lundi 07 novembre 2011 =C3=A0 09:36 +0100, Pawe=C5=82 Staszewski a =C3=
=A9crit :

> Yes after enabling NUMA I can change rhash_entries on kernel boot.
>=20
> And what is the most important for big route cahce is rhash_entries
> if route cache size exceed hash size performance will drop 6x to 8x
> So the best settings for route cache are:
> rhash_entries =3D gc_thresh =3D max_size
>=20
> Eric tell me what are the plans for removing route cache from kernel =
?
> Because as You see with route cache performance is better
> And without route cache performance is not soo good than with route=20
> cache enabled but it is stable for all situations even DDOS with 10kk=
=20
> random_ips
>=20
> So for the feature we need to prepare for lower kernel IP forwarding=20
> performance because of no route cache ?
> Or removing route cache will save some time in IP stack  processing ?
>=20

Obviously, cache removal will be possible only when performance without
it is the same.

Work is in progress, it started a long time ago.