Thursday at Linaro Connect USA 2014
Thursday at Linaro Connect began with a keynote by Dr Christos Kolias, Senior Research Scientist at Orange on Network Functions Virtualization (NFV). Dr. Kolias discussed how NFV promises to change the service provider landscape and how it has emerged as one of today’s significant trends. The day’s theme was networking and the Linaro Networking Group (LNG) extended an open invitation to attend a day of sessions focusing on accelerating the support of ARM within networking. The LNG group also had a demo day that showcased the latest developments in networking, including implementations of the OpenDataPlane (ODP) on hardware accelerated platforms, it complemented sessions on topics such as improving performance by keeping the kernel out of the way, LAVA and VLANs, and LTE EPC.
Thursday September 18, 2014
|Session||Track||Session Description||YouTube Video||Presentation||Video (Linaro Server)|
|LCU14 : LNG Keynote 1||Keynote||Link||Video||Presentation||Link|
|LCU14-400: Managing a LAVA LAB using new Debian packages||LAVA||Link||Video||Presentation||Link|
|LCU14-401: Isolation / no_hz upstreaming progress Confirmed||Networking||Link||Video||Presentation||Link|
|LCU14-402: Energy Aware Scheduling: Kernel summit update||Power Management||Link||Video||Presentation||Link|
|LCU14-404: LAVA and VLANs – complex networks on demand||Networking||Link||Video||Presentation||Link|
|LCU14-405: Linaro EMACS users BOF||N/A||Link||Video||Not available||Link|
|LCU14-406: A QuIC Take on Energy-Aware Scheduling||Power Management||Link||Video||Presentation||Link|
|LCU14-409: BoF – Kernel Testing Made Easy||Automation & Validation||Link||Video||Not available||Link|
|LCU14-410: How to build an Energy Model for your SoC||Power Management||Link||Video||Presentation||Link|
|LCU14-411: From zero to booting nanodroid with 64bit support||Android||Link||Video||Not available||Link|
Summaries from some of Thursday’s Sessions
LCU14-402: Energy Aware Scheduling: Kernel summit update
The first session of the EAS workshop was a status update from the Linaro and ARM engineers who were invited to kernel summit to attend the EAS track. The tools (idlestat and rt-app) were well-received by maintainers with some feedback on how to improve them going forward. Similarly, the maintainers were very interested in fixing the scale invariant load tracking problem which is also a requirement for tighter scheduler-cpufreq integration. Both these patchsets will be posted by ARM and Linaro respectively in the coming weeks. Scheduler and cpuidle integration involves two areas: first, saving the cpu’s current idle state in a scheduler data structure and then using it to find the best CPU for task placement and secondly, to replace the menu governor with a new IO latency tracking framework. The first patchset is already under review, the second will be posted in the coming weeks. Finally, there was some discussion around the energy model proposal details of which were covered in the following session.
LCU14-404: LAVA and VLANs – complex networks on demand
A description of the new Linaro VLAN daemon (VLANd) development effort was discussed . We were also looking for feedback and ideas for what we need to consider that we hadn’t already designed in. Started with a brief history of the LAVA Lab, followed by the networking problems we started to see as we grew, and the realisation that we needed some way to set up and tear down Virtual Networks in an automated sense, which led to the design and development of VLANd.
LCU14-406: A QuIC Take on Energy-Aware Scheduling
Qualcomm gave an excellent overview of the Qualcomm EAS solution. It covered the reasons why GTS patchset from ARM was not enough for their needs and then went into details of the design decisions of their own solution. Significant changes were made to the load tracking by replacing the per-entity load tracking with a window-based load tracking. QC uses a simpler energy model to the one proposed by ARM and uses small task packing heuristics similar to work done in Linaro which is currently on hold. QC relies heavily on governors and tunables so there is some concern about upstream plans to get rid of them.
LCU14-410: How to build an Energy Model for your SoC
The presenter walked the audience through how to go about creating an energy model for their SoC. He went into details of how to measure the various bits of energy cost to put into the model.
Images of the Linaro Networking Group Demo Day