Interview with Chad Norgan of Rackspace, about use of Open vSwitch at

Rackspace over the years.

Topics include:

Chad's role at Rackspace and what he spends his time on.

Shifts in where he spends his time as Open vSwitch has matured.

Experiments with buying and writing SDN controllers and OpenFlow flows

at Rackspace, including a Ryu-based chassis controller.

SDN in two generations of Rackspace cloud, with NVP in the second

generation.

Tracing datapath flows using tools in Open vSwitch, using

“ovs-appctl ofproto/trace”, and the value of tracing for

debugging a running system.

Suggestions for improving “ovs-appctl ofproto/trace”.

Usefulness of Open vSwitch logging.

Significant performance improvements since earlier versions, such as

moving logging out of the main thread, megaflows, and eviction

handling.

Potential appliance use of DPDK, contrasted against downside for

hypervisors of losing a core.

Thoughts about importance of 64-byte packet performance in Rackspace

environment, and potential of eBPF work going on at Cisco to help with

that.

Performance history of Open vSwitch versions as perceived by Nicira and

Rackspace, and its evolution over time as Open vSwitch was exposed to

more and more diverse production use cases.

Open vSwitch decision for version 1.11 to completely rewrite everything

in terms of megaflows, to achieve reasonable performance in important

minority of cases.

Chad's presentation on Open vSwitch performance at the Open vSwitch 2014

Fall Conference.

Open vSwitch as the “incumbent” virtual switch.

Generating good representative traffic for testing.

Ixia hardware for predictable traffic generation, removing a variable

from the testing equation.

Desire for a physical hardware switch with the flexibility of Open

vSwitch, with P4 switches as a possible route there.

“ovsdb-tool -mmm show-log” as database debugging tool.

Chad can be contacted at @chadnorgan on Twitter, as

BeardyMcBeard on the freenode IRC

network

OVS Orbit is produced by Ben Pfaff. The

intro and bumper music is Electro

Deluxe, featuring Gurdonack, copyright 2014 by My Free Mickey. The

outro music is Girls like

you, featuring Thespinwires, copyright 2014 by Stefan Kartenberg.

All content is licensed under a Creative Commons Attribution 3.0

Unported (CC BY 3.0) license.