[libvirt] [BUG] mlock support breakage

[Luiz Capitulino]

On Tue, 14 Mar 2017 19:40:38 +0100
Andrea Bolognani <abologna at redhat.com> wrote:

> It's unfortunate that the current, buggy behavior made
> it look like you didn't necessarily have to worry about
> this. If we fix it, existing guests will fail to start
> right away instead of possibly crashing in the future:
> while that's going to be very annoying in the short run,

It breaks existing guests, so it's beyond annoying.

> it's arguably better than illuding people their guests
> will be good in the long run while in reality we can't
> provide such guarantee.
> 
> Luiz mentioned the fact that you can't set the memory
> locking limit to "unlimited" with the current <hard_limit>
> element: that's something we can, and should, address.
> With that implemented, the administrator will have full
> control on the memory limit and will be able to implement
> the policy that best suits the use case at hand.

Asking <locked/> users to set <hard_limit> to "unlimited"
is a much worse solution than automatically setting the
memory lock limit to infinity in libvirt, for the reasons
I outlined in my first email.

PS: Still, we should have "unlimited" support for <hard_limit>