presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/metadata/ShardCleaner.java/ShardCleaner/getBackupShardsQueued
class ShardCleaner:    @Managed
    @Nested
    public CounterStat getBackupShardsQueued()
    {
        return backupShardsQueued;
    }