import akka.actor.ActorRef;
import akka.actor.ActorSelection;
import akka.actor.Cancellable;
+import akka.cluster.Cluster;
+import akka.cluster.Member;
+import akka.cluster.MemberStatus;
+import akka.cluster.ClusterEvent.CurrentClusterState;
import akka.pattern.Patterns;
import com.google.common.base.Optional;
import com.google.common.base.Preconditions;
import com.google.common.base.Strings;
+import com.google.common.collect.ImmutableSet;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import org.opendaylight.controller.cluster.datastore.entityownership.messages.UnregisterListenerLocal;
import org.opendaylight.controller.cluster.datastore.entityownership.selectionstrategy.EntityOwnerSelectionStrategy;
import org.opendaylight.controller.cluster.datastore.entityownership.selectionstrategy.EntityOwnerSelectionStrategyConfig;
-import org.opendaylight.controller.cluster.datastore.identifiers.ShardIdentifier;
import org.opendaylight.controller.cluster.datastore.messages.BatchedModifications;
import org.opendaylight.controller.cluster.datastore.messages.PeerDown;
import org.opendaylight.controller.cluster.datastore.messages.PeerUp;
private final EntityOwnershipShardCommitCoordinator commitCoordinator;
private final EntityOwnershipListenerSupport listenerSupport;
private final Set<MemberName> downPeerMemberNames = new HashSet<>();
- private final Map<String, MemberName> peerIdToMemberNames = new HashMap<>();
private final EntityOwnerSelectionStrategyConfig strategyConfig;
private final Map<YangInstanceIdentifier, Cancellable> entityToScheduledOwnershipTask = new HashMap<>();
private final EntityOwnershipStatistics entityOwnershipStatistics;
this.strategyConfig = builder.ownerSelectionStrategyConfig;
this.entityOwnershipStatistics = new EntityOwnershipStatistics();
this.entityOwnershipStatistics.init(getDataStore());
-
- for(String peerId: getRaftActorContext().getPeerIds()) {
- ShardIdentifier shardId = ShardIdentifier.fromShardIdString(peerId);
- peerIdToMemberNames.put(peerId, shardId.getMemberName());
- }
}
@Override
if (isLeader) {
+ // Re-initialize the downPeerMemberNames from the current akka Cluster state. The previous leader, if any,
+ // is most likely down however it's possible we haven't received the PeerDown message yet.
+ initializeDownPeerMemberNamesFromClusterState();
+
// Clear all existing strategies so that they get re-created when we call createStrategy again
// This allows the strategies to be re-initialized with existing statistics maintained by
// EntityOwnershipStatistics
strategyConfig.clearStrategies();
// Re-assign owners for all members that are known to be down. In a cluster which has greater than
- // 3 nodes it is possible for a some node beside the leader being down when the leadership transitions
- // it makes sense to use this event to re-assign owners for those downed nodes
+ // 3 nodes it is possible for some node beside the leader being down when the leadership transitions
+ // it makes sense to use this event to re-assign owners for those downed nodes.
+ Set<String> ownedBy = new HashSet<>(downPeerMemberNames.size() + 1);
for (MemberName downPeerName : downPeerMemberNames) {
- selectNewOwnerForEntitiesOwnedBy(downPeerName);
+ ownedBy.add(downPeerName.getName());
}
+
+ // Also try to assign owners for entities that have no current owner. See explanation in onPeerUp.
+ ownedBy.add("");
+ selectNewOwnerForEntitiesOwnedBy(ownedBy);
} else {
// The leader changed - notify the coordinator to check if pending modifications need to be sent.
// While onStateChanged also does this, this method handles the case where the shard hears from a
super.onLeaderChanged(oldLeader, newLeader);
}
+ private void initializeDownPeerMemberNamesFromClusterState() {
+ java.util.Optional<Cluster> cluster = getRaftActorContext().getCluster();
+ if(!cluster.isPresent()) {
+ return;
+ }
+
+ CurrentClusterState state = cluster.get().state();
+ Set<Member> unreachable = state.getUnreachable();
+
+ LOG.debug("{}: initializeDownPeerMemberNamesFromClusterState - current downPeerMemberNames: {}, unreachable: {}",
+ persistenceId(), downPeerMemberNames, unreachable);
+
+ downPeerMemberNames.clear();
+ for(Member m: unreachable) {
+ downPeerMemberNames.add(MemberName.forName(m.getRoles().iterator().next()));
+ }
+
+ for(Member m: state.getMembers()) {
+ if(m.status() != MemberStatus.up() && m.status() != MemberStatus.weaklyUp()) {
+ LOG.debug("{}: Adding down member with status {}", persistenceId(), m.status());
+ downPeerMemberNames.add(MemberName.forName(m.getRoles().iterator().next()));
+ }
+ }
+
+ LOG.debug("{}: new downPeerMemberNames: {}", persistenceId(), downPeerMemberNames);
+ }
+
private void onCandidateRemoved(CandidateRemoved message) {
LOG.debug("{}: onCandidateRemoved: {}", persistenceId(), message);
// Available members is all the known peers - the number of peers that are down + self
// So if there are 2 peers and 1 is down then availableMembers will be 2
- final int availableMembers = peerIdToMemberNames.size() - downPeerMemberNames.size() + 1;
+ final int availableMembers = getRaftActorContext().getPeerIds().size() - downPeerMemberNames.size() + 1;
LOG.debug("{}: Using strategy {} to select owner, currentOwner = {}", persistenceId(), strategy, currentOwner);
// it will first remove all its candidates on startup. If another candidate is registered during the time
// the peer is down, the new candidate will be selected as the new owner.
- selectNewOwnerForEntitiesOwnedBy(downMemberName);
+ selectNewOwnerForEntitiesOwnedBy(ImmutableSet.of(downMemberName.getName()));
}
}
- private void selectNewOwnerForEntitiesOwnedBy(MemberName downMemberName) {
+ private void selectNewOwnerForEntitiesOwnedBy(Set<String> ownedBy) {
final BatchedModifications modifications = commitCoordinator.newBatchedModifications();
- searchForEntitiesOwnedBy(downMemberName.getName(), (entityTypeNode, entityNode) -> {
+ searchForEntitiesOwnedBy(ownedBy, (entityTypeNode, entityNode) -> {
YangInstanceIdentifier entityPath = YangInstanceIdentifier.builder(ENTITY_TYPES_PATH).
node(entityTypeNode.getIdentifier()).node(ENTITY_NODE_ID).node(entityNode.getIdentifier()).
node(ENTITY_OWNER_NODE_ID).build();
private void onPeerUp(PeerUp peerUp) {
LOG.debug("{}: onPeerUp: {}", persistenceId(), peerUp);
- peerIdToMemberNames.put(peerUp.getPeerId(), peerUp.getMemberName());
downPeerMemberNames.remove(peerUp.getMemberName());
// Notify the coordinator to check if pending modifications need to be sent. We do this here
// to handle the case where the leader's peer address isn't known yet when a prior state or
// leader change occurred.
commitCoordinator.onStateChanged(this, isLeader());
+
+ if(isLeader()) {
+ // Try to assign owners for entities that have no current owner. It's possible the peer that is now up
+ // had previously registered as a candidate and was the only candidate but the owner write tx couldn't be
+ // committed due to a leader change. Eg, the leader is able to successfully commit the candidate add tx but
+ // becomes isolated before it can commit the owner change and switches to follower. The majority partition
+ // with a new leader has the candidate but the entity has no owner. When the partition is healed and the
+ // previously isolated leader reconnects, we'll receive onPeerUp and, if there's still no owner, the
+ // previous leader will gain ownership.
+ selectNewOwnerForEntitiesOwnedBy(ImmutableSet.of(""));
+ }
}
private Collection<String> getCandidateNames(MapEntryNode entity) {
return candidateNames;
}
- private void searchForEntitiesOwnedBy(final String owner, final EntityWalker walker) {
- LOG.debug("{}: Searching for entities owned by {}", persistenceId(), owner);
+ private void searchForEntitiesOwnedBy(Set<String> ownedBy, EntityWalker walker) {
+ LOG.debug("{}: Searching for entities owned by {}", persistenceId(), ownedBy);
searchForEntities((entityTypeNode, entityNode) -> {
Optional<DataContainerChild<? extends PathArgument, ?>> possibleOwner =
entityNode.getChild(ENTITY_OWNER_NODE_ID);
- if(possibleOwner.isPresent() && owner.equals(possibleOwner.get().getValue().toString())) {
+ String currentOwner = possibleOwner.isPresent() ? possibleOwner.get().getValue().toString() : "";
+ if(ownedBy.contains(currentOwner)) {
walker.onEntity(entityTypeNode, entityNode);
}
});