/**
* Execute the VMs in the simulation
*
* @param hosts
*/
public void execute(ArrayList<Host> hosts) {
// retrieve ordered list of vm allocations
ArrayList<VMAllocation> vmList = buildVmList(hosts);
// calculate the resources each VM has available
for (VMAllocation vmAllocation : vmList) {
if (vmAllocation.getVm() != null) vmAllocation.getVm().prepareExecution();
}
// prepare hosts for VM execution
for (Host host : hosts) {
// if the Host is ON
if (host.getState() == Host.HostState.ON) {
// allow the Host's CPU Scheduler to prepare for scheduling
host.getCpuScheduler().prepareScheduler();
host.getCpuScheduler().beginScheduling();
// prepare the privileged domain VM for execution
host.getPrivDomainAllocation().getVm().prepareExecution();
// instruct the Host's CPU Scheduler to run the priviledged domain VM
host.getCpuScheduler().schedulePrivDomain(host.getPrivDomainAllocation());
}
}
HashSet<VMAllocation> completedVms =
new HashSet<VMAllocation>(); // set of VMs that have completed execution
boolean notDone = true; // true while execution is not complete
// execute VMs in rounds until complete. In each round, every VM has a chance to execute
do {
notDone = false; // start by assuming done
// instruct Host CPU Schedulers to begin a round of scheduling
for (Host host : hosts) {
if (host.getState() == Host.HostState.ON) host.getCpuScheduler().beginRound();
}
// execute VMs
for (VMAllocation vmAllocation : vmList) {
// if the VM has not be executed, the VM Allocation actually contains a VM, and the host is
// ON
if (!completedVms.contains(vmAllocation)
&& vmAllocation.getVm() != null
&& vmAllocation.getHost().getState()
== Host.HostState.ON) { // ensure that a VM is instantiated within the allocation
// if the CPU scheduler has not indicated that is is COMPLETE (i.e. out of resources)
if (vmAllocation.getHost().getCpuScheduler().getState()
!= CpuScheduler.CpuSchedulerState.COMPLETE) {
// run the VM
if (vmAllocation.getHost().getCpuScheduler().processVM(vmAllocation)) {
// returned true = VM is not finished executing (still has work to complete)
notDone = true; // not done yet
} else {
// returned false = VM is done (no more work to complete)
completedVms.add(vmAllocation);
}
}
}
}
// instruct Host CPU Schedulers that the round has completed
for (Host host : hosts) {
if (host.getState() == Host.HostState.ON) host.getCpuScheduler().endRound();
}
} while (notDone); // if not done, execute another round
// instruct Host CPU Schedulers that scheduling is complete
for (Host host : hosts) {
if (host.getState() == Host.HostState.ON) {
host.getCpuScheduler().endScheduling();
host.getPrivDomainAllocation().getVm().completeExecution();
}
}
// update the resourcesInUse for each VM
for (VMAllocation vmAllocation : vmList) {
if (vmAllocation.getVm() != null) {
vmAllocation.getVm().completeExecution();
}
}
}
