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cloudius-systems / osv

OSv, a new operating system for the cloud.
osv.io
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place xen vcpus in arbitrary locations #120

Closed glommer closed 10 months ago

glommer commented 10 years ago

Xen's shared info structure only contains space for 32 vcpus. That means if we want to boot with more cpus than 32, we need to have extra space for vcpus.

The VCPUOP_register_vcpu_info hypercall can be used to that. It is not available in all hypervisors, and is very likely not available on Amazon (I haven't tested, but it is not available in the version amazon uses. They may have backported it, though...)

We should test for availability of that hypercall somehow, and use it to place extra CPUs in different locations.

wkozaczuk commented 3 years ago

Given we have a very small team of volunteers, is the ability to run OSv with more than 32 cpus on XEN still relevant? Shall we close it?

nyh commented 3 years ago

I don't see a reason to close it - it indicates a specific missing feature, and if one day somebody wants to implement it, they can get hints here. If there is any reason to suspect that Xen doesn't have this 32 cpus issue any more, we can close it. We can also add a "Xen" label to xen-specific issues and just ignore all of them :-)

wkozaczuk commented 10 months ago

It has been almost 3 years since we touched on this issue. And given I have almost no Xen know-how and we have very few volunteers and zero interest from anyone in improving our Xen support I suggest we close this issue.