presto-main/src/main/java/io/prestosql/memory/ClusterMemoryPool.java/ClusterMemoryPool/getQueryMemoryRevocableReservations
class ClusterMemoryPool:    public synchronized Map<QueryId, Long> getQueryMemoryRevocableReservations()
    {
        return ImmutableMap.copyOf(queryMemoryRevocableReservations);
    }