On Thu, Apr 28, 2016 at 07:13:42PM +0200, Florian Westphal wrote: > Once we place all conntracks into same table iteration becomes more > costly because the table contains conntracks that we are not interested > in (belonging to other netns). > > So don't bother scanning if the current namespace has no entries. > > Signed-off-by: Florian Westphal <fw@xxxxxxxxx> > --- > net/netfilter/nf_conntrack_core.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c > index 29fa08b..f2e75a5 100644 > --- a/net/netfilter/nf_conntrack_core.c > +++ b/net/netfilter/nf_conntrack_core.c > @@ -1428,6 +1428,9 @@ void nf_ct_iterate_cleanup(struct net *net, > > might_sleep(); > > + if (atomic_read(&net->ct.count) == 0) > + return; This optimization gets defeated with just one single conntrack (ie. net->ct.count == 1), so I wonder if this is practical thing. At the cost of consuming more memory per conntrack, we may consider adding a per-net list so this iteration doesn't become a problem. > while ((ct = get_next_corpse(net, iter, data, &bucket)) != NULL) { > /* Time to push up daises... */ > if (del_timer(&ct->timeout)) > -- > 2.7.3 > > -- > To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html