[Cake] faster scheduling, maybe

David Lang david at lang.hm
Mon Jun 6 14:48:52 EDT 2016

On Mon, 6 Jun 2016, Dave Taht wrote:

> http://info.iet.unipi.it/~luigi/papers/20160511-mysched-preprint.pdf

I don't think so.

They don't even try for fairness between flows, they are just looking at 
fairness between different VMs. they tell a VM that it has complete access to 
the NIC for a time, then give another VM complete access to the NIC. At best 
they put each VMs traffic into a different hardware queue in the NIC.

This avoids all AQM decisions on the part of the host OS, because the packets 
never get to the host OS.

The speed improvement is by bypassing the host OS and just having the VMs 
deliver packets directly to the NIC. This speeds things up, but at the cost of 
any coordination across VMs. Each VM can run fq_codel but it's much corser 
timeslicing between VMs.

David Lang

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