Hi Salil,
(replying to an off-list email from Salil...)
You suggested proposing a talk on the hotplug stuff for kvm forum, yes we can co-present it, but we'll need to discuss it here. Let me know if you plan to submit this today, or I need to do it. I finish work at roughly 6pm UK time.
For a title I suggest: "Supporting hotplug on architectures that don't".
I had a stab at the abstract before you wrote yours: vCPU hotplug is used by orchestration managers to pre-create VMs, and scale them correctly when a workload is deployed. Architecture support for adding CPUs to an existing system is complex, and not feasible to standardise without hardware. This talk covers the use-cases, difficulties, and a proposed way of supporting this on architectures that lack physical CPU hotplug.
Comparing it to what you've written. I'm not sure the abstract needs any technical details. We can mention the history in the talk, but I don't think its useful to dwell on it.
We'll need to come up with slides, my suggested outline is something like: * The x86 history: CPU hotplug being supported before virtualisation. * Why vCPU hotplug is used for on x86 (kata containers, kubernetes, cloud orchestration) * Why that ACPI mechanism wouldn't work for arm64: we can't support hotplug virtualisation without real hardware. (not future proof) * What the actual requirements are. * Changes to PSCI and arm64-linux to support all this in a future proof way. * How physical CPU hotplug would work at the same time
[* Slides on the Qemu details and complexities.]
Something to be aware is of is that arm want a clear split in the presentation between the kernel side of it, and your Qemu work.
Thanks,
James