/**
* Compute the new partition IDs to add to the cluster based on the new topology.
*
* @param zk Zookeeper client
* @param topo The new topology which should include the new host count
* @return A list of partitions IDs to add to the cluster.
* @throws JSONException
*/
public static List<Integer> getPartitionsToAdd(ZooKeeper zk, JSONObject topo)
throws JSONException {
ClusterConfig clusterConfig = new ClusterConfig(topo);
List<Integer> newPartitions = new ArrayList<Integer>();
Set<Integer> existingParts = new HashSet<Integer>(getPartitions(zk));
// Remove MPI
existingParts.remove(MpInitiator.MP_INIT_PID);
int partsToAdd = clusterConfig.getPartitionCount() - existingParts.size();
if (partsToAdd > 0) {
hostLog.info(
"Computing new partitions to add. Total partitions: "
+ clusterConfig.getPartitionCount());
for (int i = 0; newPartitions.size() != partsToAdd; i++) {
if (!existingParts.contains(i)) {
newPartitions.add(i);
}
}
hostLog.info("Adding " + partsToAdd + " partitions: " + newPartitions);
}
return newPartitions;
}
public List<Integer> getIv2PartitionsToReplace(JSONObject topology) throws JSONException {
ClusterConfig clusterConfig = new ClusterConfig(topology);
hostLog.info(
"Computing partitions to replace. Total partitions: " + clusterConfig.getPartitionCount());
Map<Integer, Integer> repsPerPart = new HashMap<Integer, Integer>();
for (int i = 0; i < clusterConfig.getPartitionCount(); i++) {
repsPerPart.put(i, getReplicaCountForPartition(i));
}
List<Integer> partitions =
computeReplacementPartitions(
repsPerPart,
clusterConfig.getReplicationFactor(),
clusterConfig.getSitesPerHost(),
clusterConfig.getPartitionCount());
hostLog.info("IV2 Sites will replicate the following partitions: " + partitions);
return partitions;
}