Commodity distributed systems

创建分布式系统是一项重大的工程实践，设计成本往往高达数百万美元，操作成本则高出数倍。事实上，在北美，仅维持现有计算系统运行的总成本每年就超过400亿美元。尽管有这笔费用，计算机系统通常是不安全和不可靠的。这个问题的唯一主要原因是，这些系统的复杂性超出了除最优秀的人类专家之外的所有人的能力。即使是安装联网的家庭计算机也常常需要大量的系统知识。证据表明，这种复杂性是与生俱来的。随着时间的推移，随着我们构建更大的系统并相互连接这些系统，这个问题将变得更糟，而不是更好。

The creation of a distributed system is a major engineering exercise, often costing many millions of dollars to design, and several times more to operate. Indeed, the total cost in North America just to keep existing computing systems functioning exceeds $40 billion annually. In spite of this expense, computer systems are typically insecure and unreliable. The single major cause of this problem is that the complexity of these systems exceeds the abilities of all but the very best of human experts. Even the installation of a networked home computer often requires significant systems knowledge. The evidence suggests that this complexity is inherent. Over time this problem will get worse not better, as we build larger systems and inter-connect those systems.