I have a lot of bridges for tagged VLANs.
It needs 5 secs on each to bring up.
That means it needs more than an hour to start a system if there are 1000 VLANs configured.
I think they all can be brought up in parallel, because they depends on vmbr0000.
# systemd-analyze blame
1min 49.366s networking.service
2.971s systemd-udev-settle.service
2.149s dev-mapper-VG1\x2dSYSTEM.device
#grep bridge_ports /etc/network/interfaces.d/lan | wc
21 42 691
Example:
iface left
rx 4096
tx 4096
mtu 9000
iface right
rx 4096
tx 4096
mtu 9000
auto b_lan
iface b_lan
bond_mode 802.3ad
bond-xmit-hash-policy layer2+3
bond_miimon 100
bond_updelay 400
bond_downdelay 200
bond_slaves left right
mtu 9000
# up ifconfig $IFACE txqueuelen 10000
auto vmbr0000
iface vmbr0000 inet manual
bridge_ports b_lan
bridge_stp off
bridge_maxwait 5
#RAW-LAN: tagged backbone
auto vmbr2001
iface vmbr2001 inet manual
bridge_ports vmbr0000.2001
bridge_stp off
bridge_maxwait 5
#VLAN #2001: Guest
I have a lot of bridges for tagged VLANs. It needs 5 secs on each to bring up. That means it needs more than an hour to start a system if there are 1000 VLANs configured.
I think they all can be brought up in parallel, because they depends on vmbr0000.