/**
* Get a runnable node in the given rack that is not present in the excluded list
*
* @param requestedNode the node to look up rack locality for
* @param excluded the list of nodes to ignore
* @return the runnable node from the rack satisfying conditions, null if the node was not found
*/
public ClusterNode getRunnableNodeForRack(RequestedNode requestedNode, Set<String> excluded) {
NodeContainer nodeContainer = requestedNode.getRackNodes();
getRunnableNodeForRackCounter += 1;
if (nodeContainer == null) {
return null;
}
synchronized (nodeContainer) {
if (nodeContainer.isEmpty()) {
return null;
}
if (getRunnableNodeForRackCounter % RACK_SHUFFLE_PERIOD == 0) {
// This balances more evenly across nodes in a rack
nodeContainer.shuffle();
}
for (ClusterNode node : nodeContainer) {
if (excluded == null || !excluded.contains(node.getHost())) {
if (resourceLimit.hasEnoughResource(node)) {
return node;
}
}
}
}
return null;
}
/**
* Get runnable node local to the given host
*
* @param requestedNode the requested node that needs local scheduling
* @return the node that is local to the host, null if there are no runnable nodes local to the
* host
*/
public ClusterNode getRunnableNodeForHost(RequestedNode requestedNode) {
// there should only be one node per host in the common case
NodeContainer nodeContainer = requestedNode.getHostNodes();
if (nodeContainer == null) {
return null;
}
synchronized (nodeContainer) {
if (nodeContainer.isEmpty()) {
return null;
}
for (ClusterNode node : nodeContainer) {
if (resourceLimit.hasEnoughResource(node)) {
return node;
}
}
}
return null;
}
