[libvirt] [RFC] vhost-user + shared memory + NUMA

[Pavel Fedin]

 Hello!

> Historically QEMU had a pointless check on the path passed in, to enforce
> that it was only hugetlbfs, so could not just pass in a regular tmpfs
> file. I think we removed that in QEMU 2.5. I think it is a valid enhance
> <memoryBacking> to allow specification of "shared" memory backing which
> would be mapping to a regular tmpfs.
> 
> I don't think we should magically do anything based on existance of
> vhost-user though - changes in way the guest memory is allocated should
> always require explicit user configuration.

 Ok, then would it be a good compromise if we require <memoryBacking>, and only implicitly add "shared" if we have vhost-user
devices? This way we would not change the way the guest memory is allocated.
 IMHO being able to manually specify "shared" both in <numa> and in <memoryBacking> would be ambiguous.

Kind regards,
Pavel Fedin
Senior Engineer
Samsung Electronics Research center Russia