presto-main/src/main/java/io/prestosql/memory/ClusterMemoryPool.java/ClusterMemoryPool/getInfo
class ClusterMemoryPool:    public synchronized MemoryPoolInfo getInfo()
    {
        return new MemoryPoolInfo(
                totalDistributedBytes,
                reservedDistributedBytes,
                reservedRevocableDistributedBytes,
                ImmutableMap.copyOf(queryMemoryReservations),
                ImmutableMap.copyOf(queryMemoryAllocations),
                ImmutableMap.copyOf(queryMemoryRevocableReservations));
    }