Far from being a
risky implementation for system designers, NVMe is growing up fast.
Developed and backed by the consortium, the standard satisfied rigorous
scrutiny and evaluation before its publication. A strong ecosystem has
already developed to speed and aid implementation of reliable
high-performance NVMe solutions, including NVMe enterprise flash memory
controllers that support SSD suppliers in transitioning to
high-throughput, low-latency designs. IDT, Intel, and LSI have developed
standards-based NVMe software drivers, and test and measurement
specialists such as LeCroy and Agilent offer NVMe protocol analyzers.
ecosystem provides a framework and support to SSD developers; including
an enterprise 2.5-in. SSD form factor specification that was released
in December 2011. This standard, which has received broad industry
support, also focuses on issues such as connector specifications and hot
pluggability to give high availability and important user
serviceability benefits. Additionally, standard open-source NVMe
compliance suite and UNH’s recently-formed NVMe Interoperability Lab
help ensure compliance and interoperability.
Figure 2: NVMe 2.5-in. SSD reference design is based on IDT’s new 16-channel PCIe enterprise flash controller.
NVMe usage models
are several usage models for NVMe PCIe SSDs. These help to illustrate
the real-world benefits of the host controller interface standard:
High performance storage in a concentrated/central storage system—In a
tiered enterprise storage system, using an array of PCIe SSDs for the
high-performance tier can greatly enhance the overall storage system
performance. The seamless interoperability between the switches used for
system connectivity and the PCIe flash controllers are key. By
employing NVMe supported by compatible flash memory controllers such as
16- or 32-channel devices, developers can remove performance bottlenecks
and reduce latency—in some instances by over 50%.
direct-attached cache—Optimized for read intensive workloads,
single-host server flash caching solutions based on PCIe SSDs reduce
latency and increase throughput dramatically in enterprise storage
applications. As server direct-attached cache is installed on more
servers in an environment, the result is a highly scalable I/O
processing model. By continually and automatically determining which
data is in most frequently used and then caching it on the server-based
PCIe card, the performance of read intensive applications can be
significantly improved. Server direct-attached cache solutions are
typically able to reduce response times from milliseconds to
microseconds by bypassing the overhead of network storage access.
Employing NVMe helps to bring out the best performance potential in the
technology by effectively tightening its integration into the system.
Once again, NVMe ensures that throughput is maximized and latency is
minimized, while using standard software drivers.
high performance drive—These applications utilize front-loadable PCIe
SSDs in the standardized 2.5 inch format. This approach provides a
serviceability level equivalent to traditional drives, eases integration
and enhances scalability. An NVMe interface allows the hot-swappable
SSDs to connect directly to the PCIe host bus while maximizing
performance and offering standard enterprise-class features. PCIe
provides a direct connection between the solid-state storage, the CPU
and system memory.
Supported by an established and growing
ecosystem, and a range of dedicated devices, the NVMe scaleable host
control interface standard is able to provide the performance necessary
to maximize the potential of PCIe SSDs in enterprise applications.
growing demand for high performance enterprise storage is partially
addressed with existing proprietary PCIe SSDs; however, prior to the
availability of NVMe and compatible devices such as IDT’s flash
controllers, proprietary drivers have presented a significant obstacle
for broad adoption. Now, SSD developers have a standard high-performance
host control interface, enterprise flash controllers, support
framework, and tools required to clear those performance bottlenecks and
meet the ever-increasing demands for accessing vast amounts of data at
1. V. Filks and J. Unsworth,
“When Implementing SSDs, Ease of Use Is More Important Than
Cost-Effectiveness,” Gartner (Dec 2011).
2. Gamess TableIO workload
is a computational test. System type: E5-2680 2-Socket Romley-EP QUAL
SDP, BIOS: rev x040, CPUs: Two 8-Core C1, 2.7 GHz, UNCORE: 2.7 GHz, QPI:
8.0 GT/sec, RAM: 32GB, DDR3-1333 MHz (8 x 4GB DIMMs), Disks: root
mounted on 7200 RPM SATA disk/home1 mounted on a 4-disk RAID0 file
system, Red Hat Enterprise Linux Server release 6.2, 220.127.116.11 Santiago,
Fusion-IO 640GB IODrive FS1-003-641-CS-0001, NVMe 64GB.
About the author
Kam Eshghi is Sr. Director of Marketing in Enterprise Computing Division of IDT. Kam leads IDT’s business strategy, marketing and business development for flash controllers and PCIe switches. Kam drove the creation of IDT’s PCIe Enterprise Flash Controller product line and helped establish IDT as a leader in this market. Kam holds a M.S. in Electrical Engineering & Computer Science from Massachusetts Institute of Technology, and a Master’s in Business Administration and B.S. in Electrical Engineering & Computer Science both from University of California at Berkeley.