presto-main/src/main/java/io/prestosql/memory/ClusterMemoryManager.java/ClusterMemoryManager/getMemoryPoolInfo
class ClusterMemoryManager:    public synchronized Map<MemoryPoolId, MemoryPoolInfo> getMemoryPoolInfo()
    {
        ImmutableMap.Builder<MemoryPoolId, MemoryPoolInfo> builder = new ImmutableMap.Builder<>();
        pools.forEach((poolId, memoryPool) -> builder.put(poolId, memoryPool.getInfo()));
        return builder.build();
    }