/**
* Get a runnable node.
*
* @param requestedNode The request information.
* @param maxLevel The maximum locality level that we can go to.
* @param type The type of resource.
* @param excluded The excluded nodes.
* @return The runnable node that can be used.
*/
public ClusterNode getRunnableNode(
RequestedNode requestedNode,
LocalityLevel maxLevel,
ResourceType type,
Set<String> excluded) {
ClusterNode node = null;
RunnableIndices r = typeToIndices.get(type);
// find host local
node = r.getRunnableNodeForHost(requestedNode);
if (maxLevel == LocalityLevel.NODE || node != null) {
return node;
}
node = r.getRunnableNodeForRack(requestedNode, excluded);
if (maxLevel == LocalityLevel.RACK || node != null) {
return node;
}
// find any node
node = r.getRunnableNodeForAny(excluded);
return node;
}
/**
* Find the best matching node for this host subject to the maxLevel constraint
*
* @param host the host of the request
* @param maxLevel the max locality level to consider
* @param type the type of resource needed on the node
* @param excluded the list of nodes to exclude from consideration
* @return the runnable node satisfying the constraints
*/
public ClusterNode getRunnableNode(
String host, LocalityLevel maxLevel, ResourceType type, Set<String> excluded) {
if (host == null) {
RunnableIndices r = typeToIndices.get(type);
return r.getRunnableNodeForAny(excluded);
}
RequestedNode node = resolve(host, type);
return getRunnableNode(node, maxLevel, type, excluded);
}
