+const double virt_overhead = 1; // 0.95
+
+static void host_state_change(s4u::Host const& host)
+{
+ if (not host.is_on()) { // just turned off.
+ std::vector<s4u::VirtualMachine*> trash;
+ /* Find all VMs living on that host */
+ for (s4u::VirtualMachine* const& vm : VirtualMachineImpl::allVms_)
+ if (vm->get_pm() == &host)
+ trash.push_back(vm);
+ for (s4u::VirtualMachine* vm : trash)
+ vm->shutdown();
+ }
+}
+
+static void add_active_exec(s4u::Actor const&, s4u::Exec const& task)
+{
+ s4u::VirtualMachine* vm = dynamic_cast<s4u::VirtualMachine*>(task.get_host());
+ if (vm != nullptr) {
+ VirtualMachineImpl* vm_impl = vm->get_impl();
+ vm_impl->active_tasks_ = vm_impl->active_tasks_ + 1;
+ vm_impl->update_action_weight();
+ }
+}
+
+static void remove_active_exec(s4u::Actor const&, s4u::Exec const& task)
+{
+ s4u::VirtualMachine* vm = dynamic_cast<s4u::VirtualMachine*>(task.get_host());
+ if (vm != nullptr) {
+ VirtualMachineImpl* vm_impl = vm->get_impl();
+ vm_impl->active_tasks_ = vm_impl->active_tasks_ - 1;
+ vm_impl->update_action_weight();
+ }
+}
+
+static s4u::VirtualMachine* get_vm_from_activity(kernel::activity::ActivityImpl const& act)
+{
+ auto* exec = dynamic_cast<kernel::activity::ExecImpl const*>(&act);
+ return exec != nullptr ? dynamic_cast<s4u::VirtualMachine*>(exec->get_host()) : nullptr;
+}
+
+static void add_active_activity(kernel::activity::ActivityImpl const& act)
+{
+ s4u::VirtualMachine* vm = get_vm_from_activity(act);
+ if (vm != nullptr) {
+ VirtualMachineImpl *vm_impl = vm->get_impl();
+ vm_impl->active_tasks_ = vm_impl->active_tasks_ + 1;
+ vm_impl->update_action_weight();
+ }
+}
+
+static void remove_active_activity(kernel::activity::ActivityImpl const& act)
+{
+ s4u::VirtualMachine* vm = get_vm_from_activity(act);
+ if (vm != nullptr) {
+ VirtualMachineImpl *vm_impl = vm->get_impl();
+ vm_impl->active_tasks_ = vm_impl->active_tasks_ - 1;
+ vm_impl->update_action_weight();
+ }
+}
+
+VMModel::VMModel()
+{
+ all_existing_models.push_back(this);
+ s4u::Host::on_state_change.connect(host_state_change);
+ s4u::Exec::on_start.connect(add_active_exec);
+ s4u::Exec::on_completion.connect(remove_active_exec);
+ kernel::activity::ActivityImpl::on_resumed.connect(add_active_activity);
+ kernel::activity::ActivityImpl::on_suspended.connect(remove_active_activity);
+}