Comment # 7 on bug 905421 from Marius Tomaschewski

This is not the end of this story, but an improvement & workaround.
git master seems to work so far to create 100 vlans on a nic and a
bridge on each vlan -- here results from a slow machine:

# cat /proc/cpuinfo | grep -E "cpu cores|model name" | head -2
model name  : Intel(R) Atom(TM) CPU  330   @ 1.60GHz
cpu cores   : 2
# systemd-analyze blame | head -1
    1min 32.383s wicked.service
# wicked ifstatus --brief all | grep -E "br.*up$|eth1[.].*enslaved$" | wc -l
202
# wicked ifstatus --brief all | grep -Ev "br.*up$|eth1[.].*enslaved$" 
lo              up
eth0            up
wlan0           device-unconfigured
wlan1           device-unconfigured
eth1            up

An i7 box needs ~15s mostly because it requests dhcp4 and dhcp6 on a nic.

Git master RPMs are currently building and will appear at:
  http://download.opensuse.org/repositories/network:/wicked:/master/

The buffer size can be set in the config now (here using defaults):

cat >/etc/wicked/local.xml <<EOF
<config>
  <netlink-events>
    <receive-buffer-length>1048576</receive-buffer-length>
    <!-- 0 causes to use a libnl default of 4 pages / 16k: -->
    <message-buffer-length>0</message-buffer-length>
  </netlink-events>
</config>
EOF

and on >0, it is reported as info log message. The lengths are applied
using SO_RCVBUFFORCE now (see also /proc/sys/net/core/rmem_*).