/**
* Get any runnable node that is not one of the excluded nodes
*
* @param excluded the list of nodes to ignore
* @return the runnable node, null if no runnable node can be found
*/
public ClusterNode getRunnableNodeForAny(Set<String> excluded) {
double avgLoad = loadManager.getAverageLoad(type);
// Make two passes over the nodes. In the first pass, try to find a
// node that has lower than average number of grants on it. If that does
// not find a node, try looking at all nodes.
for (int pass = 0; pass < 2; pass++) {
for (Map.Entry<String, NodeContainer> e : hostToRunnableNodes.entrySet()) {
NodeContainer nodeContainer = e.getValue();
if (nodeContainer == null) {
continue;
}
synchronized (nodeContainer) {
if (nodeContainer.isEmpty()) {
continue;
}
for (ClusterNode node : nodeContainer) {
if (excluded == null || !excluded.contains(node.getHost())) {
if (resourceLimit.hasEnoughResource(node)) {
// When pass == 0, try to average out the load.
if (pass == 0) {
if (node.getGrantCount(type) < avgLoad) {
return node;
}
} else {
return node;
}
}
}
}
}
}
}
return null;
}
