[LARTC] prio qdisc broken?

[Andy Furniss]

Joerg Pommnitz wrote:
> Hello all,
> I might make a fool out of me, but I think the prio qdisc doesn't work  as
> advertised in any document I could lay my hands on.
> 
> The following tests and observations were made with Linux kernel 2.6.20.21.
>  This makes it up-to-date in the 2.6.20.x kernel family.

If it's kernel version you are unlucky - I just tested with a 2.6.19-rc6 
and a 2.6.21.1 and it seems OK.

Echo replies don't work, and they haven't on others versions as well, 
but this could be deliberate anti dos plus I am not testing forwarded 
traffic.

> 
> My problem was that the link quality reported by the olsr.org olsrd  degraded
> depending on the amount of payload traffic was transferred through an
> adhoc/mesh interface. The LQ is calculated from the packet loss of LQ  Hello
> packets sent through this interface. To make sure normal traffic  does not
> interfere with this value, olsrd sets the TOS field to 0x10  (Minimize-Delay)
> by default. In theory this should give olsr traffic the highest  priority on the link.
> 

Even if you fix it I don't think it will help wireless using just prio.

There are/will be extensions to prio AIUI - multiqueue which if the 
wireless driver supports it, prio bands will map to hardware/link layer 
prio bands on the device.

Andy.