private boolean reroute(RoutingAllocation allocation) {
boolean changed = false;
// first, clear from the shards any node id they used to belong to that is now dead
changed |= deassociateDeadNodes(allocation);
// create a sorted list of from nodes with least number of shards to the maximum ones
applyNewNodes(allocation);
// elect primaries *before* allocating unassigned, so backups of primaries that failed
// will be moved to primary state and not wait for primaries to be allocated and recovered
// (*from gateway*)
changed |= electPrimariesAndUnassignedDanglingReplicas(allocation);
// now allocate all the unassigned to available nodes
if (allocation.routingNodes().hasUnassigned()) {
changed |= shardsAllocators.allocateUnassigned(allocation);
// elect primaries again, in case this is needed with unassigned allocation
changed |= electPrimariesAndUnassignedDanglingReplicas(allocation);
}
// move shards that no longer can be allocated
changed |= moveShards(allocation);
// rebalance
changed |= shardsAllocators.rebalance(allocation);
assert RoutingNodes.assertShardStats(allocation.routingNodes());
return changed;
}
/**
* Only handles reroute but *without* any reassignment of unassigned shards or rebalancing. Does
* make sure to handle removed nodes, but only moved the shards to UNASSIGNED, does not reassign
* them.
*/
public RoutingAllocation.Result rerouteWithNoReassign(ClusterState clusterState, boolean debug) {
RoutingNodes routingNodes = clusterState.routingNodes();
// shuffle the unassigned nodes, just so we won't have things like poison failed shards
routingNodes.unassigned().shuffle();
RoutingAllocation allocation =
new RoutingAllocation(
allocationDeciders,
routingNodes,
clusterState.nodes(),
clusterInfoService.getClusterInfo());
allocation.debugDecision(debug);
boolean changed = false;
// first, clear from the shards any node id they used to belong to that is now dead
changed |= deassociateDeadNodes(allocation);
// create a sorted list of from nodes with least number of shards to the maximum ones
applyNewNodes(allocation);
// elect primaries *before* allocating unassigned, so backups of primaries that failed
// will be moved to primary state and not wait for primaries to be allocated and recovered
// (*from gateway*)
changed |= electPrimariesAndUnassignedDanglingReplicas(allocation);
if (!changed) {
return new RoutingAllocation.Result(false, clusterState.routingTable());
}
return new RoutingAllocation.Result(
true,
new RoutingTable.Builder()
.updateNodes(routingNodes)
.build()
.validateRaiseException(clusterState.metaData()));
}
