Just FYI: I'm tangentially aware of internal Google code that: - expects a bonding device running HTB with non-zero txqueuelen - wants to remove HTB and get a noqueue interface (the normal default for bonding)
The code currently removes HTB, which gets us to mq, sets txqueuelen to 0, adds a pfifo, removes the pfifo, which gets us to noqueue. After this patch this would ?possibly? break (adding pfifo, would change txqueuelen, so when we remove it we wouldn't end up with noqueue). >From what I fuzzily recall, HTB with txquelelen == 0 drops traffic hard, while pfifo continues to function, hence the ordering... Obviously our code can be fixed, but I'm worried there's a more generic backwards compatibility problem here. (note: this is mostly about 3.11 and 4.3 and might no longer be relevant with 4.10... maybe the new kernel's default qdisc selection logic doesn't depend on txqueuelen and checks the flag instead???)
