The Impact of Disruptive Technologies on the Professional Storage Marketby Johan De Gelas on August 5, 2013 9:00 AM EST
The Winds of Change
My reason for writing this article is that a wind of change is blowing through the storage market. The success of cloud storage such as Amazon S3 and Syncplicity has opened the way to new methods of archiving, making backups, and even disaster recovery. But the biggest disruptor is of course flash memory, and more specifically PCIe SSDs.
PCIe SSDs are not bandwidth limited by the SATA/SAS wiring and (if implemented well) protocol overhead. As a result, PCIe drives have up to three times as many channels of flash memory. And well-designed PCIe SSDs do not have to carry the burden of RAID controllers and protocols that were architectured for hard drives with completely different characteristics than flash memory. But even if they use a PCIe/SAS bridge, PCIe SSDs offer higher reliability and vastly superior performance than the best enterprise drives. But there is much more going on.
As PCIe SSDs offer large capacities (up to 10TB!) and performance in a very small form factor, they open new markets. It is interesting to see the completely new solutions that are now available, solutions that are much better suited for certain workloads. One example of a workload where traditional SANs fall short is virtual desktops.
Virtual desktops like Xendesktop or VMware View have been promising significant energy and cost savings, but these savings almost never materialize in reality. The energy saving claims made a few years ago were ridiculous; they were based on the assumption that we are still using power hogging desktops. Replace those with thin clients and you magically get massive energy savings.
The reality is that most of the IT professionals already use a 20-30W portable instead of an old 150W desktop, and the extra server load was not helping save energy either. Even if portables were not used, many business desktops today sip small amounts of energy. And if there was any miraculous energy saving, the additional complex storage system would be the final blow. The end result of desktop virtualization is often higher instead of lower energy bills. But perhaps worse is that knowledge workers hated most of the virtual desktops project with a passion. Suddenly several actions that used to complete without any noticeable response time became laggy.
Although there were serious costs savings if your desktop deployment and management was just organized chaos, every organization that replaced PCs with virtual desktops faced the need for huge investments. As lots of people boot up their virtual desktop in the morning, massive amounts of data is written and read in a rather random way: the so called “boot storm”. The solution was to boot up the desktops in a staggered way, tens of minutes before the arrival of the users, and to perform all kinds of special optimizations all over the software stack. But that is hardly more than a band-aid: what about unexpected hot fix patches, or what if people arrive a little bit earlier on occasion?
Data source: NetApp News 2013
Astute readers understand that the administration of virtual desktops is quite a bit more complex than the traditional setup with roaming profiles and saving files on a centralized file server. Only the most recent and high-end SANs could really deal with these specific requirements. Granted, some of the essential storage tasks like backup and archiving are a lot easier once you have a SAN in place… but mostly after you have invested in all kinds of expensive management software. When you start to invest in a complex SAN platform, the costs seem to multiply like rabbits.
In short, although a fast SAN seemed to be an enabler, they were also a deal breaker in the virtual desktop world. They're too slow and/or too expensive, and they're also power hungry.
Several companies feel they have a much better alternative and it is very interesting to see how the Fusion–IO and Intel PCIe SSDs are being turned into innovative and specialized alternatives for the typical SAN solution. Let's discuss a few of these over the next several pages.