narendly commented on a change in pull request #362: The WAGED rebalancer
cluster model implementation
URL: https://github.com/apache/helix/pull/362#discussion_r310170701
##########
File path:
helix-core/src/main/java/org/apache/helix/controller/rebalancer/waged/model/ClusterModel.java
##########
@@ -19,9 +19,131 @@
* under the License.
*/
+import org.apache.helix.HelixException;
+import org.apache.helix.model.IdealState;
+
+import java.util.Collections;
+import java.util.Map;
+import java.util.Set;
+import java.util.stream.Collectors;
+
/**
- * A placeholder before we have the implementation.
- *
* This class wraps the required input for the rebalance algorithm.
*/
-public class ClusterModel { }
+public class ClusterModel {
+ private final ClusterContext _clusterContext;
+ // Map to track all the assignable replications. <Resource Name,
Set<Replicas>>
+ private final Map<String, Set<AssignableReplica>> _assignableReplicas;
+ // The index to find the replication information with a certain state.
<Resource, <Replica Key (resource, partition, state), Replica>>
+ // Note that the identical replicas are dedupe in the index.
+ private final Map<String, Map<String, AssignableReplica>>
_assignableReplicaIndex;
+ private final Map<String, AssignableNode> _assignableNodeMap;
+
+ // Records about the previous assignment
+ private final Map<String, IdealState> _baselineAssignment;
+ private final Map<String, IdealState> _bestPossibleAssignment;
+
+ /**
+ * @param clusterContext The initialized cluster context.
+ * @param assignableReplicas The replications to be assigned.
+ * Note that the replicas in this list shall
not be included while initializing the context and assignable nodes.
+ * @param assignableNodes The active instances.
+ * @param baselineAssignment The recorded baseline assignment.
+ * @param bestPossibleAssignment The current best possible assignment.
+ */
+ ClusterModel(ClusterContext clusterContext, Set<AssignableReplica>
assignableReplicas,
+ Set<AssignableNode> assignableNodes, Map<String, IdealState>
baselineAssignment,
+ Map<String, IdealState> bestPossibleAssignment) {
+ _clusterContext = clusterContext;
+
+ // Save all the to be assigned replication
+ _assignableReplicas = assignableReplicas.stream()
+ .collect(Collectors.groupingBy(AssignableReplica::getResourceName,
Collectors.toSet()));
+
+ // Index all the replicas to be assigned. Dedup the replica if two
instances have the same resource/partition/state
+ _assignableReplicaIndex = assignableReplicas.stream().collect(Collectors
+ .groupingBy(AssignableReplica::getResourceName, Collectors
+ .toMap(AssignableReplica::toString, replica -> replica,
+ (oldValue, newValue) -> oldValue)));
+
+ _assignableNodeMap = assignableNodes.stream()
+ .collect(Collectors.toMap(AssignableNode::getInstanceName, node ->
node));
+
+ _baselineAssignment = baselineAssignment;
+ _bestPossibleAssignment = bestPossibleAssignment;
+ }
+
+ public ClusterContext getContext() {
+ return _clusterContext;
+ }
+
+ public Map<String, AssignableNode> getAssignableNodes() {
+ return _assignableNodeMap;
+ }
+
+ public Map<String, Set<AssignableReplica>> getAssignableReplicas() {
+ return _assignableReplicas;
+ }
+
+ public Map<String, IdealState> getBaseline() {
+ return _baselineAssignment;
+ }
+
+ public Map<String, IdealState> getBestPossibleAssignment() {
+ return _bestPossibleAssignment;
+ }
+
+ /**
+ * Propose the assignment to the cluster model.
Review comment:
Rephrase? This description doesn't make sense. Say "Try to make an
assignment for a given replica on the given instance. Note that this may not
show up in the final assignment - this assignment may be released and
re-assigned elsewhere."
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
[email protected]
With regards,
Apache Git Services
