Current Overview

VMware is best known for its hypervisor technology, and to that end, they have pretty much defined the entire market, and by all accounts, continues to and will continue to be the market leader.

At VMworld 2013, Pat Gelsinger, CEO of VMware, announced that VMware is setting its sights on adjacent and supporting technologies – namely networking and storage. In his speech, Gelsinger discussed how the future of the data center will be software-defined and be all about the application.

A number of vendors, including the following announced storage for virtualized environments that use NAND-based flash storage technology:

• Fusion-IO;
• Greenbytes;
• Nimbus Data Systems (announced last week, to avoid the glut of announcements expected at VMworld);
• Skyera.

As the density of guest virtual machines, whether they are server applications or in the special use case of virtual desktop infrastructure (VDI), desktop images, the underlying storage subsystem will ultimately create a bottleneck. Flash storage technology can minimize the differential in performance between DRAM, CPU and traditional magnetic hard disk drives (HDDs).

There is a tremendous amount of material already written about the benefits of flash and solid state storage.

Where and how flash storage is deployed is important. There are several schools – some believe that flash storage should be placed as close to the processor as possible, while others believe that flash should be a shared network resource. The important thing to recognize is that there is no silver bullet.

Each of the approaches have their relative merits and detractions, and each should be evaluated based on the specific environment in which the technology will be deployed.

Neuraspective™

Users should take note that flash and other solid state storage technology is a performance enhancing technology. There are users who can benefit from all-flash arrays. For most users, the introduction of some flash can and will reduce capital investments in the long term, and improve service levels.

Multiple studies over the last 20 years have consistently shown that if users replaced around 5% of their capacity with flash, it can significant boost performance, and at the same time, slow down capital investment in additional storage capacity. The key to this magic 5% number is not that you simply replace 5% of your capacity with flash. A detailed analysis needs to be performed as to how

the capacity is to be distributed, and which server(s) will benefit from the performance boost.

Despite all the buzz around solid state storage, its deployment must be purposeful. Solid state disks (SSDs) and other flash media are not simply the next generation of storage media. SSDs do not represent an investment in capacity. It is an investment in performance. Perhaps over time, the cost of flash can be reduced enough to replace HDDs. But for now, there is not enough evidence that NAND-flash has the same endurance and reliability in all user cases.