What is NVMe?

NVMe, or Non-Volatile Memory Express, is a high-performance, host controller interface designed for solid-state drives (SSDs). It takes advantage of the parallelism and low latency features of PCIe (Peripheral Component Interconnect Express) to deliver exceptional performance and efficiency. NVMe enables communication between the storage interface and the system’s CPU using high-speed PCIe sockets without the limitations of form factor, unlocking the true potential of SSDs. Since NVMe utilizes PCIe sockets, it transfers 25x more data than the SATA equivalent. NVMe represents a significant leap from the traditional Serial ATA (SATA) interface, revolutionizing how data is stored, accessed, and transferred. 

What is SATA?

SATA (Serial Advanced Technology Attachment) is a protocol that prescribes how data is moved between a computer and a storage device, such as a hard disk drive (HDD). SATA and Serial Attached SCSI (SAS) protocols were the industry standard before the introduction of NVMe. The first flash-based SSDs used traditional SATA/SAS physical interfaces, protocols, and form factors to minimize changes in the existing hard drive (HDD)-based enterprise server/ storage systems. Although SATA SSDs had better performance than HDDs, they did not fully exploit the potential of flash memory due to the limitations of the SATA interface. The first SSDs were relatively slow, transferring up to 150MB/s with SATA I. Even though the SATA bus has evolved, SATA III can only transfer up to 600MB/s.

Transition to PCIe and NVMe:

To overcome the performance limitations of SATA, SSDs started adopting the PCIe (Peripheral Component Interconnect Express) interface. PCIe provides a high-speed, point-to-point connection between the NVMe SSD and the host system, enabling faster data transfer rates and significantly reducing latency. PCIe 3.0’s total throughput is 16Gbps while PCIe 4.0 has double the throughput of PCIe 3.0. It offers up to 16 lanes and can transfer data at up to 32,000MB/s.

Image source: Kingston

NVMe was first introduced in 2011 as a new storage protocol designed to leverage the capabilities of SSDs. The NVMe protocol utilizes parallel, low-latency data paths to the underlying media, like high-performance processor architectures. This offers significantly higher performance and lower latencies compared to SAS and SATA protocols. NVMe can support multiple I/O queues, up to 64K with each queue having 64K entries. Legacy SAS and SATA can only support single queues and each can have 254 & 32 entries respectively. NVMe also communicates directly with the system CPU, giving it incredible speeds due to its compatibility. SAS and SATA protocols consume many CPU cycles to make data available to applications. Thus, NVMe not only accelerates existing applications that require high performance, but also enables new applications and capabilities for real-time workload processing in the data center and at the Edge.

NVMe SSD Form Factor

NVMe drives come in various new form factors to accommodate different types of devices.

• U.2 – formerly known as SFF-8639, is a 2.5-inch form factor designed for NVMe SSDs. These are more costly storage devices with higher performance and endurance typically found in data center/ server applications. 

• M.2 – M.2 is a small form factor designed for space-constrained devices such as laptops and tablets. It connects directly to the motherboard using the M.2 slot, eliminating the need for cables. M.2 SSDs come in different lengths and widths. 22 refers to the width and 30/42/80/110 refer to the length in millimetres. Currently, M.2 2280 supports SATA, it is also the most common NVMe SSD form factor for NVMe. As technology advances and becomes smaller, this may change.

• Add-in PCIe cards – Some NVMe SSDs are designed as PCIe add-in cards that can be inserted into a PCIe slot on the motherboard or expansion card. These cards provide high-speed data transfer rates and are often used in high-performance computing and server environments.

• EDSFF: Enterprise and Datacenter SSD Form Factor (EDSFF) is a new form factor designed specifically for data centers. EDSFF SSDs come in different sizes, including E1.S and E1.L, providing higher storage density and improved cooling capabilities. They are optimized for scalability, hot-swapping, and efficient airflow in dense storage systems.

Image Source: Western Digital

In summary, NVMe is a major advancement compared to the traditional SATA interface. NVMe SSD offers significantly faster speeds, lower latency, enhanced scalability, and better performance optimization compared to SATA. As the demand for faster and more responsive storage solutions continues to grow, NVMe has emerged as the go-to choice for users seeking optimal performance and efficiency. 

Dataplugs All-Flash NVMe Server is equipped with Intel Xeon Rocket-Lake CPU and lightning-fast datacenter-grade NVMe SSD. Feel free to contact us via LiveChat or Telegram to learn more about our dedicated server plans.