PowerEdge PCIe Express Flash SSD

PowerEdge Express Flash Server
Narrow the gap between server and storage performance with Dell™ PowerEdge™ Express Flash PCIe solid-state storage device (SSD). Avoiding the mechanical limitations of a hard disk drive, Dell’s PowerEdge Express Flash PCIe-SSD can help break through I/O (input/output) bottlenecks for latency-sensitive applications.

Dell Express Flash technology is currently available for purchase on performance 2-socket and 4-socket PowerEdge server platforms, including the R920R820, R720, R620, T620, M620 and M820.

PowerEdge Express Flash PCIe-SSDFlash technology
Solid-state drives (SSDs) use solid-state NAND flash memory to store data rather than the rotating magnetic recording media of hard disk drives (HDDs). Even the latest HDDs are performance-limited by the spindle speed of the disk (15K rpm). Solid-state technology does not suffer from the mechanical constraints of HDDs because it has no moving parts, providing reliable, ultra-fast, low-power and cost-effective storage devices. Nonvolatile NAND flash replace mechanical drives in solid-state storage solutions, designed to provide fast, reliable, low-power and cost-effective storage devices. Two types of non-volatile NAND types flash are in use today:
  • Single-level cell (SLC) NAND — SLC contains 1 bit per cell and is best suited for performance-intensive applications where high-write endurance is required, and cost is not a factor.
  • Multilevel cell (MLC) NAND — MLC contains 2 bits per cell, and is used for applications having high-capacity requirements and/or minimal need for write endurance, and provides a lower cost alternative to SLC-based solutions.

SSD formats

SAS/SATA SSDs are similar to HDDs in that they use the same interface and therefore are accessed by the system through the same OS driver stack. While SAS/SATA solid-state storage devices offer significantly better performance over standard rotating-media HDDs, their performance can be limited by the latency and bottlenecks inherent in the driver stack. A single Express Flash drive can achieve up to 10.5x more database transactions per second than HDD storage.

PCIe solid-state storage (SSS), on the other hand, is directly connected to the PCIe bus. The bus provides a direct connection between the PCIe-SSS and the CPU, as well as system memory. This tightly coupled connection provides a storage environment that has lower latency than a SAS/SATA SSD.

Dell PowerEdge Express Flash PCIe-SSD
The PowerEdge Express Flash PCIe-SSD is a high-performance storage device built with enterprise-class NAND flash designed for solutions requiring low latency, high input/output operations per second (IOPS) and enterprise-class storage reliability and serviceability. The Express Flash PCIe-SSD is a PCIe Gen2/Gen3-compliant device (depending on server type) that can be configured as storage cache or as a primary storage device in demanding enterprise environments, such as enterprise blade and rack servers, video-on-demand servers, web accelerators and virtualization appliances.
PowerEdge Express Flash PCIe-SSD

Standards-based development
Today, PCIe-SSDs are standardized as half-height/half-length (low-profile), full-height/half-length and full-height/full-length PCIe cards. While performance is impressive, the cards do not facilitate fast, cost-effective serviceability. To counter this limitation, Dell was a founding member of the SSD Form Factor Workgroup (SSD FF WG) driving the specification and standards for the 2.5" form factor and the 2.5" PCIe-SSD connector, which facilitates a device package that enables a serviceability model equivalent to today's hard disk drives (HDDs).

Dell also is a founding member of the Non Volatile Memory Express (NVM Express) consortium helping drive a standardized high-performance host controller interface for PCIe SSDs designed for current and next-generation non-volatile memory.

By providing standards-based PCIe-SSD technology and enabling high availability, serviceability, ease of integration and enhanced scalability, the end customer will have a wider choice of options, can limit expensive customization and can plan for the future more efficiently.

Drive form factor
The SSD FF WG is working toward a specification that leverages the current 2.5" HDD form factor standard. The aim is to enable enclosure flexibility while supporting the new connector definition and expanding the power envelope to support higher performance.

PowerEdge Express Flash PCIe-SSD
On your latest generation PowerEdge™ server enabled for PCIe-SSD, the PowerEdge Express Flash 2.5" PCIe-SSD form factor allows it to be plugged into a device bay. Up to four Express Flash devices can be connected, depending on your server.

PowerEdge Server

Hot-swap behavior
Dell has implemented hot-swap features and capabilities in the Express Flash PCIe-SSDs that are already employed by today’s hard disk drives. The intention is to help make serviceability and system scaling as quick and easy as possible. Dell is enabling the reliability and serviceability features that customers expect with standard HDDs to be a reality with PCIe-SSDs.

The Dell PowerEdge™ Express Flash PCIe-SSD is the industry’s first hot-swappable PCIe SSD, supporting such hot-swap functions as:

  • Orderly insertion, which enables you to insert a drive into a running system where a similar device has not been previously inserted from the time it was last booted. Dell systems that support PCIe SSDs are correctly configured to handle PCIe resource balancing in the event of a hot insertion.
  • Orderly removal, which allows you to remove a device from a running system. Before physically removing the device, you must notify the system that the device is about to be removed.
  • Orderly swap, which lets you remove a device from the system and replace it with an identical supported device.
PowerEdge Express Flash PCIe-SSD

High performance
The Dell PowerEdge Express Flash PCIe-SSD enables outstanding IOPS performance. Dell Express Flash technology can deliver up to 1000x improvement in IOPS over traditional HDDs.Our first generation SLC based product delivered sequential throughput on reads and writes of up to 1.8/1.2GBps. Our second generation NVMe Express Flash devices are designed to deliver 3.0/1.4GBps at PCIe Gen3. In addition, the Dell PowerEdge Express Flash PCIe-SSD does not burden the server’s CPU and memory with NAND flash management overhead. Flash management is provided by the device controller running firmware on a high-performance ASIC that resides within the PCIe-SSD. This architecture offers superb IOPS and throughput performance without "borrowing" server resources.

Since NAND SSDs have a finite number of program and erase cycles, Dell warrants the PowerEdge Express Flash PCIe-SSD to a maximum amount of data written to the SSD in total bytes written. The SSD monitors these cycles and Dell software management applications notify you when the warranty limits are reached


You can apply Express Flash PCIe-SSD technology to a number of applications, including:
•Online transactional processing (OLTP)
•Online analytical processing (OLAP)
•Collaborative (SharePoint) environments
•Virtualization (Hyper-V)

Express Flash PCIe-SSDs integrate with servers at the system bus and kernel level, creating a new flash storage cache/tier that can be used as a second-level database buffer cache for frequently read blocks or to store database objects, which requires low latency and high IO rates.

PowerEdge Express Flash PCIe-SSD