private void assignMapsWithLocality(List<Container> allocatedContainers) {
// try to assign to all nodes first to match node local
Iterator<Container> it = allocatedContainers.iterator();
while(it.hasNext() && maps.size() > 0){
Container allocated = it.next();
Priority priority = allocated.getPriority();
assert PRIORITY_MAP.equals(priority);
// "if (maps.containsKey(tId))" below should be almost always true.
// hence this while loop would almost always have O(1) complexity
String host = allocated.getNodeId().getHost();
LinkedList<TaskAttemptId> list = mapsHostMapping.get(host);
while (list != null && list.size() > 0) {
if (LOG.isDebugEnabled()) {
LOG.debug("Host matched to the request list " + host);
}
TaskAttemptId tId = list.removeFirst();
if (maps.containsKey(tId)) {
ContainerRequest assigned = maps.remove(tId);
containerAssigned(allocated, assigned);
it.remove();
JobCounterUpdateEvent jce =
new JobCounterUpdateEvent(assigned.attemptID.getTaskId().getJobId());
jce.addCounterUpdate(JobCounter.DATA_LOCAL_MAPS, 1);
eventHandler.handle(jce);
hostLocalAssigned++;
if (LOG.isDebugEnabled()) {
LOG.debug("Assigned based on host match " + host);
}
break;
}
}
}
// try to match all rack local
it = allocatedContainers.iterator();
while(it.hasNext() && maps.size() > 0){
Container allocated = it.next();
Priority priority = allocated.getPriority();
assert PRIORITY_MAP.equals(priority);
// "if (maps.containsKey(tId))" below should be almost always true.
// hence this while loop would almost always have O(1) complexity
String host = allocated.getNodeId().getHost();
String rack = RackResolver.resolve(host).getNetworkLocation();
LinkedList<TaskAttemptId> list = mapsRackMapping.get(rack);
while (list != null && list.size() > 0) {
TaskAttemptId tId = list.removeFirst();
if (maps.containsKey(tId)) {
ContainerRequest assigned = maps.remove(tId);
containerAssigned(allocated, assigned);
it.remove();
JobCounterUpdateEvent jce =
new JobCounterUpdateEvent(assigned.attemptID.getTaskId().getJobId());
jce.addCounterUpdate(JobCounter.RACK_LOCAL_MAPS, 1);
eventHandler.handle(jce);
rackLocalAssigned++;
if (LOG.isDebugEnabled()) {
LOG.debug("Assigned based on rack match " + rack);
}
break;
}
}
}
// assign remaining
it = allocatedContainers.iterator();
while(it.hasNext() && maps.size() > 0){
Container allocated = it.next();
Priority priority = allocated.getPriority();
assert PRIORITY_MAP.equals(priority);
TaskAttemptId tId = maps.keySet().iterator().next();
ContainerRequest assigned = maps.remove(tId);
containerAssigned(allocated, assigned);
it.remove();