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Computer - NVMe Memory

What is Non-volatile Memory Express (NVMe)?

NVMe（非易失性存储器 Express）是一个协议，它使用 PCI Express（PCIe）界面将固态硬盘（SSD）存储器链接到服务器或 CPU。它是连接到计算机主板的非易失性存储器 Express（NVMe）的最快速、最流行的协议。NVMe 于 2011 年由一群 IT 专业人员开发，该设备是 SATA 和串行附加 SCSI（SAS）协议的替代品，它提供了更高的吞吐量，以便获得更快速、更可靠的性能。除了存储和技术进步之外，NVMe 有助于加速物联网（IoT）、人工智能（AI）和机器学习（ML）等关键技术的开发。

NVMe (Non-Volatile Memory Express) is a protocol that uses the PCI Express (PCIe) interface to link solid-state drive (SSD) storage to servers or CPUs. It is the fastest and most popular protocol for connecting to a computer’s motherboard’s non-volatile memory express (NVMe). NVMe was developed in 2011 by a group of IT professionals; this device is an alternative to SATA and Serial Attached SCSI (SAS) protocols which provides higher throughput for faster and more reliable performance. In addition to storage and technology advancements, NVMe helped to accelerate the development of critical technologies like as the Internet of Things (IoT), artificial intelligence (AI), and machine learning (ML).

NVMe 协议专用于数据传输，每个输入/输出操作的系统开销较低，且每秒操作次数较少。它用于带有闪存的 SSD。NVMe 解决 SATA 界面和通信协议中的瓶颈。NVMe 技术使用 PCIe 总线代替 SATA 总线，从而释放了存储设备的巨大带宽潜力。NVMe 技术通过跨不同平台提高经济性、性能和兼容性，为存储设备解锁了不同的可能性。

The NVMe protocol is dedicated to data transfer with low system overheads per input/output operation per second. It is used in SSDs with flash memory. NVMe addresses the bottlenecks in the SATA interface and communication protocols. NVMe technology uses the PCIe bus instead of the SATA bus to unleash massive bandwidth potential for storage devices. NVMe technology unlocks different possibilities for storage devices by increasing economy, performance, and compatibility across different platforms.

近年来数据存储技术的进步促使组织和个人从传统硬盘驱动器（HDD）转向快速数据传输和低延迟固态硬盘（SSD）。SSD 和 NVMe 是两种不同类型的驱动器，可以互补使用。SSD 是基于半导体的存储器，包括闪存，而 NVMe 是一个数据传输协议，它在带有闪存的 SSD 中降低了每个输入/输出操作的系统开销，且每秒操作次数更少。预期 NVMe 技术将在未来成为新的行业标准。

Recent technical developments in data storage have pushed organizations and individuals to move from traditional hard disk drives (HDDs) to fast data transmission, and lower-latency solid-state drives (SSDs). SSD and NVMe are two different types of drives that can be used to complement each other. SSDs are semiconductor-based storage that includes flash storage, and NVMe is a data transfer protocol that uses reduced system overheads per input/output operation per second in SSDs with flash memory. It is expected that the NVMe technology will become the new industry standard in the upcoming time.

Why NVMe is Important?

NVMe 具有外设组件互连 Express（PCIe）总线，可以实现高达 20 千兆字节每秒（Gbps）的传输速度。NVMe 设备不需要电源来保持其存储器。与其他技术不同，NVMe 存储可以使用 PCIe 插槽直接连接到计算机的 CPU，并使驱动器的闪存能够通过 PCIe 运行。

NVMe has a Peripheral Component Interconnect Express (PCIe) bus which can achieve transfer speeds of up to 20 gigabytes per second (Gbps). Power is not required for the NVMe device to retain its memory. Unlike other technologies, NVMe storage can connect directly to a computer’s CPU using a PCIe socket and enable the drive’s flash memory to function through PCIe.

NVMe 技术具有快速的数据传输速度并允许并行性和轮询；NVMe SSD 可以优化响应时间和写入速度，并减少延迟以避免 CPU 瓶颈。此外，NVMe 技术比流行的小型计算机系统接口（SCSI）消耗的功率更少。

NVMe technology has fast data transfer speeds and allows for parallelism and polling; NVMe SSDs can optimize response times, and write speeds, and reduce latency to avoid CPU bottlenecks. Additionally, NVMe technology uses less power than the popular Small Computer System Interface (SCSI).

Characteristics of NVMe

NVMe 的一些关键特征如下：

Some of the key characteristics of NVMe are as follows −

  1. High Throughput and Low Latency − NVMe leverages the high-speed PCIe bus for latency which makes faster data transfer rates.

  2. Performance Enhancement − Its low latency and high-speed data transfer features significantly improve the performance of storage systems.

  3. Scalability − The structural design of NVMe makes it scalable to improve performance by providing compatibility with future storage advancements.

  4. Cost Efficiency − Its higher performance and durability typically result in long-term cost advantages due to increased productivity and decreased downtime.

  5. Future-proofing − NVMe is highly extensible and compatible with all emerging persistent memory technologies.

How does NVMe Work?

NVMe 是一种存储传输技术，它允许您快速访问来自 SSD 等闪存存储设备的数据。它允许闪存使用高速的外设组件互连 Express（PCIe）总线直接与计算机进行通信，从而实现快速、高吞吐量和并行数据传输。NVMe 通过高速外围组件互连 Express（PCIe）总线在存储接口和系统 CPU 之间进行通信。NVMe 协议被开发为与快速媒体一起使用。

NVMe is a storage transfer technology that allows you to quickly access data from flash memory storage devices like SSDs. It allows flash memory to communicate directly with a computer using a high-speed peripheral component interconnect express (PCIe) bus, resulting in quick, high-throughput, and parallel data transfer. NVMe communicates between a storage interface and a system CPU via a high-speed Peripheral Component Interconnect Express (PCIe) bus. The NVMe protocol was developed to work with fast media.

NVMe 的工作始于主机；它们编写 I/O 命令。NVMe 控制器检索并执行 I/O 命令队列，然后返回 I/O 完成队列，随后向主机中断。与标准传输协议（例如串行附加 SCSI (SAS) 和串行 ATA (SATA)）相比，主机记录 I/O 完成队列并清除门寄存器，它可以减少开销。NVMe 针对非均匀内存访问 (NUMA) 进行了优化，这意味着它可以在多个 CPU 内核之间处理队列。

NVMe’s work starts with the host; they write I/O commands. The NVMe controller retrieves and executes I/O command queues, then returns I/O completion queues, followed by an interrupt to the host. The host logs I/O completion queues and clears the door register. It reduces overhead as compared to standard transfer protocols such as serial attached SCSI (SAS) and serial ATA (SATA), NVMe is optimized for non-uniform memory access (NUMA), which means it can handle queues across multiple CPU cores.

Advantages of NVMe

NVMe 的一些主要优点如下：

Some of the key advantages of NVMe are as follows −

  1. NVMe technology gives storage, speed and compatibility features.

  2. It uses PCIe sockets which makes faster data transmission.

  3. NVMe communicates directly with the system.

  4. NVMe drives work with all major operating systems regardless of form factor.

  5. It is most suitable to utilise SSDs and communicate between the storage interface and the system’s CPU using PCIe.

  6. Its performance is significantly higher.

  7. NVMe is specifically intended for SSDs and will eventually become the next industry standard.