It's a distributed memory caching system which Facebook (and a ton of other sites) use as a caching layer between the web servers and MySQL servers (since database access is relatively slow).

它是一个分布式的内存缓存系统，Facebook(包含其他很多网站)用它作为Web服务器和MySQL服务器之间的缓存层(因为数据库访问相对比较慢)。

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Generally, the memory hierarchy follows the access time with the fast CPUregisters at the top and the slow hard drive at the bottom.

一般来说，内存层次结构如下的访问时间与快速的CPU寄存器顶部和缓慢的硬盘驱动器在底部。

youdao

Generally, the memory hierarchy follows the access time with the fast CPUregisters at the top and the slow hard drive at the bottom.

一般来说，内存层次结构如下的访问时间与快速的CPU寄存器顶部和缓慢的硬盘驱动器在底部。

youdao