??展望由非易失性设备构成的未来存储

Edward Sharp

        “愿你生活的时代充满趣味”。

不知您是否注意到，而今的IT世界已然如此，充斥着诸如云、移动、大数据、内存数据库、NoSQL、远程直接内存訪问（RDMA）、叠瓦式磁记录（SMR）硬盘、非易失性存储（NVM）以及其它不胜列数的新技术。正是因为这些新科技与技术让使用者能以更精简的资源来实现更为强大的功能，我们面临的世界正经历着天翻地覆的变化。这种变革对现有的行业既是一种威胁，但还有一方面，对于敏捷、专注而果敢的公司而言，恰恰是难得的机遇。

         对于存储行业的公司来讲，NVM是一支无可匹敌的变革力量。硬盘驱动器（HDD）盘踞存储介质层已长达数十年。随着时间的推移，速度日渐不足（尤其是依照每GB来计算）、容量日益庞大而价格日下。闪存固态盘（SSD）赫然出现，改变了一切：微妙级的延迟带来数量级的改善；为提升性能而设置的一排排主轴由整架的SSD所代替。功耗、散热及噪声等方面均大幅减少；同一时候，已经占领统治地位的大公司也受到了来自初创公司的巨大挑战。

       可是，NVM事实上是内存，而大家一直在讲NVM作为外部存储怎样怎样！

正如我的同事StephenBates以前指出的, “不要再将NVM看成高速存储，而把它当作（较慢的）内存“。

在现下的新世界中，当CPU能够直接訪问永久性存储时，计算机的架构就能够又一次设计和想象。

这不再是科幻小说的情节。MIT的聪明人已经验证了带有闪存内存的20台server的性能全然堪比配有DRAM的40台server。这项实验昭示着未来的方向。

       这一趋势对于客户而言，影响十分深长，由于其意味着客户在基础设施上的投入将得到如何的回报。然而，这场变革须要在整个生态圈中全面的革新。从应用一直到设备层面。让我们携手努力吧！

Re-imagining Storage with Non-Volatile Memory

      “May you live in interesting times.” Ifyou haven’t noticed, IT is already there, with cloud, mobile, big data,in-memory, NoSQL, Remote Direct Memory Access (RDMA), Shingled MagneticRecording (SMR) drives, Non-Volatile Memory (NVM), and the list goes on. Ourlandscape is undergoing massive disruption as new technologies and techniquesenable customers to do more with less. This disruption is a threat toexisting businesses, and an opportunity for the fast, the focused, and thebold.

          For those of us in the storage business, there is nobigger disruption than NVM. After decades of hard disk drives (HDDs)owning the storage media layer, getting slower (particularly on aper-GB-basis), fatter and cheaper each year, along came flash solid statedrives (SSDs) to change everything:  milliseconds of latency improved byorders of magnitude; racks of spindles for performance replaced with a shelf ofSSDs; power, heat and noise reduced significantly; and incumbents disrupted bystart-ups.

         But NVM is memory, and we’ve justbeen talking about NVM as storage! As my colleague Stephen Bates hasnoted before, “Let’s stopthinking about NVM as fast storage and start thinking about it as (slow)memory.” In this new world, computer architectures canbe re-imagined, with data available in persistent memory right off theCPU. This isn’t science fiction. The bright folks at MIT haverecently demonstrated 20 servers with flash memory performing as well as 40servers with DRAM. This is a harbinger of thingsto come.

        This will have profound implicationsfor what customers get for the money they put into theirinfrastructure. However, it requires changes throughout the stack, fromapplications to devices. Let’s get to work!