Subject: Takes > 1 second to delete macvlan with global IPv6 address on it.

From: Ben Greear <[email-masked]>
Date: Mon, 08 Nov 2010 16:20:22 -0800

This is on an otherwise lightly loaded 2.6.36 + hacks system, 12 physical interfaces,
and two VETH interfaces.

It's much faster to delete an interface when it has no IPv6 address:

[root@ct503-60 lanforge]# time ip link add link eth5 up name eth5#0 address 00:00:00:00:00:01 type macvlan

real	0m0.005s
user	0m0.001s
sys	0m0.004s
[root@ct503-60 lanforge]# time ip link delete eth5#0

real	0m0.033s
user	0m0.001s
sys	0m0.005s
[root@ct503-60 lanforge]# ip link add link eth5 up name eth5#0 address 00:00:00:00:00:01 type macvlan

[root@ct503-60 lanforge]# ip -6 addr add 2002::1/64 dev eth5#0
[root@ct503-60 lanforge]# time ip link delete eth5#0

real	0m1.030s
user	0m0.000s
sys	0m0.013s

Funny enough, if you explicitly remove the IPv6 addr first it seems
to run at normal speed (adding both operation's times together)

[root@ct503-60 lanforge]# ip link add link eth5 up name eth5#0 address 00:00:00:00:00:01 type macvlan
[root@ct503-60 lanforge]# ip -6 addr add 2002::1/64 dev eth5#0
[root@ct503-60 lanforge]# time ip -6 addr delete 2002::1/64 dev eth5#0

real	0m0.001s
user	0m0.000s
sys	0m0.001s
[root@ct503-60 lanforge]# time ip link delete eth5#0

real	0m0.028s
user	0m0.001s
sys	0m0.005s

Take it easy,
Ben

-- 
Ben Greear <[email-masked]>
Candela Technologies Inc  http://www.candelatech.com