Re: [Bloat] Buffer bloat at the sender

[d@taht.net (Dave Täht)]

Juliusz Chroboczek <Juliusz.Chroboczek@pps.jussieu.fr> writes:

>> I have been looking over the mq qdisc,
>
> Do you understand what it's supposed to do?

The documentation for it is in the Linux tree under 
Documentation/networking/multiqueue.txt

My understanding is that it is a general purpose mechanism to get
traffic into a driver (notably a wireless one) that has multiple queues
implemented, in the hope that classified traffic can then line up with
one of the more appropriate traffic classifications in the 802.11*
standards. [1][2]

It does not seem to be widely used at present, and the example in
the documentation is overgeneralized and does not hint at this use.

There are also all sorts of other interesting hacks^H^H^H^H^H attempts
for a reliable delivery/timeliness compromise in the mac layer in the
802.11 standards, including frame aggregation and the like.

The latest 802.11* draft is now open for review to IEEE members. [3]

How all this stuff interacts in the real world is somewhat undefined.

I'm way too far below this level of the stack to care at present, but
seeing some scripts that actually tried to wedge wireless udp/tcpip
traffic into more appropriate queues at the driver level would be
interesting.


-- 
Dave Taht
http://nex-6.taht.net

[1] http://en.wikipedia.org/wiki/IEEE_802.11e-2005
[2] http://www.intel.com/network/connectivity/resources/doc_library/white_papers/30376201.pdf
[3] http://www.ieee802.org/11/