**Build scan:**
https://gradle-enterprise.elastic.co/s/xvwrlxusnxdgu/tests/:qa:rolling-upgrade:v8.6.1%23oneThirdUpgradedTest/org.elasticsearch.upgrades.SnapshotBasedRecoveryIT/testSnapshotBasedRecovery

**Reproduction line:**
```
./gradlew ':qa:rolling-upgrade:v8.6.1#oneThirdUpgradedTest' -Dtests.class="org.elasticsearch.upgrades.SnapshotBasedRecoveryIT" -Dtests.method="testSnapshotBasedRecovery" -Dtests.seed=32151106DB58AD22 -Dtests.bwc=true -Dtests.locale=en-MT -Dtests.timezone=Asia/Colombo -Druntime.java=17
```

**Applicable branches:**
main

**Reproduces locally?:**
Didn't try

**Failure history:**
https://gradle-enterprise.elastic.co/scans/tests?tests.container=org.elasticsearch.upgrades.SnapshotBasedRecoveryIT&tests.test=testSnapshotBasedRecovery

**Failure excerpt:**
```
java.lang.AssertionError: timed out waiting for green state for index [snapshot_based_recovery] cluster state [{
  "cluster_name" : "v8.6.1",
  "cluster_uuid" : "ETWjuovuQXC6pr6CN8pJXA",
  "version" : 391,
  "state_uuid" : "y7ss0aZLQvab9JIDk7jppg",
  "master_node" : "tsyOGVI1T5iBSTLS0zL29A",
  ...
```
server/src/main/java/org/elasticsearch/cluster/routing/allocation/allocator/DesiredBalanceComputer.java
import org.elasticsearch.cluster.routing.RoutingNodes;
import org.elasticsearch.cluster.routing.ShardRouting;
import org.elasticsearch.cluster.routing.UnassignedInfo;
import org.elasticsearch.cluster.routing.allocation.RoutingAllocation;
import org.elasticsearch.cluster.routing.allocation.command.MoveAllocationCommand;
import org.elasticsearch.cluster.routing.allocation.decider.Decision;
import org.elasticsearch.common.metrics.MeanMetric;
import org.elasticsearch.common.settings.ClusterSettings;
import org.elasticsearch.common.settings.Setting;
import org.elasticsearch.core.Strings;
import org.elasticsearch.core.TimeValue;
import org.elasticsearch.index.shard.ShardId;
import org.elasticsearch.threadpool.ThreadPool;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Queue;
import java.util.Set;
import java.util.TreeMap;
import java.util.TreeSet;
import java.util.function.Predicate;
import static java.util.stream.Collectors.toSet;
import static java.util.stream.Collectors.toUnmodifiableSet;
/**
 * Holds the desired balance and updates it as the cluster evolves.
 */
public class DesiredBalanceComputer {