What a mess.
What’s faster: PV, HVM, HVM with PV drivers, PVHVM, or PVH? Cloud computing providers using Xen can offer different virtualization “modes”, based on paravirtualization (PV), hardware virtual machine (HVM), or a hybrid of them. As a customer, you may be required to choose one of these. So, which one?
Wow, this is excellent work. A formal verification of Tim Peters’ TimSort failed, resulting in a bugfix:
While attempting to verify TimSort, we failed to establish its instance invariant. Analysing the reason, we discovered a bug in TimSort’s implementation leading to an ArrayOutOfBoundsException for certain inputs. We suggested a proper fix for the culprit method (without losing measurable performance) and we have formally proven that the fix actually is correct and that this bug no longer persists.