From: Eric Dumazet <eric.dumazet@gmail.com>
To: Ajith Adapa <adapa.ajith@gmail.com>
Cc: netdev@vger.kernel.org
Subject: Re: Regarding Routing cache
Date: Thu, 17 Nov 2011 07:26:54 +0100 [thread overview]
Message-ID: <1321511214.3274.25.camel@edumazet-laptop> (raw)
In-Reply-To: <CADAe=+K8bf_VOe=KszDZRqZnxQH2VFS3C05mpG=RarN+R5BSbA@mail.gmail.com>
Please dont top post on netdev
Le jeudi 17 novembre 2011 à 11:34 +0530, Ajith Adapa a écrit :
> Hi,
>
> Actually I have doubt with IPv6 related packets.
>
> In case of IPv6 packet in ip6_route_output function is called for
> destination related information.
> where ip6_route_output calls "fib6_rule_lookup" function. Why lookup
> is done in fib table instead of routing cache in case of IPv6 packet ?
>
> In case of IPv4 packet ... ip_route_output checks in routing cache and
> if there is a cache miss then it checks the fib table.
>
IPv6 has no routing cache, and wont have one, since we are trying to
remove IPv4 routing cache :)
>
>
>
> On Thu, Nov 17, 2011 at 10:30 AM, Ajith Adapa <adapa.ajith@gmail.com> wrote:
> > Hi,
> >
> > I have a small doubt regarding routing cache in linux kernel.
> >
> > It seems ip_route_connect is the way we have to access routing cache
> > entries. In case of all locally generated packets I see that struct
> > dst_entry is filled up with a lookup in routing cache.
> >
> > What about in case of forwarding packets ? I dont see any usage of
> > routing cache mechanism to fill up the struct dst_entry. So it seems
> > we directly check the fib_rules or fib table to fill the structure.
> > If it is true then it would be very slow right ?
> >
> > Sorry if I am wrong about above findings. Do correct me if I am wrong about it ?
> >
> > Regards,
> > Ajith
> >
> --
next prev parent reply other threads:[~2011-11-17 6:26 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-11-17 5:00 Regarding Routing cache Ajith Adapa
2011-11-17 6:04 ` Ajith Adapa
2011-11-17 6:26 ` Eric Dumazet [this message]
[not found] ` <CADAe=+Jc0YinguPhTuv3sNA2bgEuuTpY9ocE7-_z-uKnsyC7Lw@mail.gmail.com>
2011-11-17 7:26 ` Eric Dumazet
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