Re: Question about vlans, bonding, etc.

[Eric Dumazet <eric.dumazet@gmail.com>]

Le lundi 03 mai 2010 à 17:06 -0700, George B. a écrit :
> Watching the "Receive issues with bonding and vlans" thread brought a
> question to mind.  In what order should things be done for best
> performance?
> 
> For example, say I have a pair of ethernet interfaces.  Do I slave the
> ethernet interfaces to the bond device and then make the vlans on the
> bond devices?
> Or do I make the vlans on the ethernet devices and then bond the vlan
> interfaces?
> 
> In the first case I would have:
> 
> 
> 
> bond0.3--|     |------eth0
>              bond0
> bond0.5--|     |------eth1
> 
> The second case would be:
> 
>       |------------------eth0.5-----|
>       |          |-------eth0.3---eth0
> bond0  bond1
>       |          |-------eth1.3---eth1
>       |------------------eth1.5-----|
> 
> I am using he first method currently as it seemed more intuitive to me
> at the time to bond the ethernets and then put the vlans on the bonds
> but it seems life might be easier for the vlan driver if it is bound
> directly to the hardware.  I am using Intel NICs (igb driver) with 4
> queues per NIC.
> 
> Would there be a performance difference expected between the two
> configurations?  Can the vlan driver "see through" the bond interface
> to the
> hardware and take advantage of multiple queues if the hardware
> supports it in the first configuration?

Unfortunatly, first combination is not multiqueue aware yet.

You'll need to patch bonding driver like this if your nics have 4
queues :

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 85e813c..98cc3c0 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -4915,8 +4915,8 @@ int bond_create(struct net *net, const char *name)
 
        rtnl_lock();
 
-       bond_dev = alloc_netdev(sizeof(struct bonding), name ? name : "",
-                               bond_setup);
+       bond_dev = alloc_netdev_mq(sizeof(struct bonding), name ? name : "",
+                               bond_setup, 4);
        if (!bond_dev) {
                pr_err("%s: eek! can't alloc netdev!\n", name);
                rtnl_unlock();