Linux IPv6 routing strange behaviour

[Hannes Frederic Sowa]

On Thu, Aug 15, 2013 at 03:15:15PM +0200, Hannes Frederic Sowa wrote:
> On Thu, Aug 15, 2013 at 04:06:11PM +0300, Max Tulyev wrote:
> > On 15.08.13 15:14, Hannes Frederic Sowa wrote:
> > > 
> > > You can also monitor routing insertion/deletion with ip -6 monitor route.
> > > 
> > 
> > Yes! I think it shows the problem more. There are a lot of this errors:
> 
> I don't see timestamp but I guess you have a massive churn in the ip6_fib
> because of the deletion and immediate insertion of prefixes.
> 
> > netlink receive error No buffer space available (105)
> 
> netlink are sockets, too, and they can run out of receive
> buffer. Try ip -rc with a higher value then 1048576. Max value is
> /proc/sys/net/core/rmem_max/rmem_max (you can increase this, too).
> 
> Thanks for the dumps, I will have a closer look later today.

Btw. recent patches could help to speed up gc:

https://git.kernel.org/cgit/linux/kernel/git/davem/net.git/commit/net/ipv6/ip6_fib.c?id=2ac3ac8f86f2fe065d746d9a9abaca867adec577
https://git.kernel.org/cgit/linux/kernel/git/davem/net.git/commit/net/ipv6/ip6_fib.c?id=49a18d86f66d33a20144ecb5a34bba0d1856b260

Maybe you can give them a try.

Greetings,

  Hannes