by Woody Hutsell, http://www.appICU.com
In the old days, real men didn’t eat broccoli and the storage solutions we implemented coped effectively with only a few related types of workload profiles. Those days are dead. Now, as data centers move toward virtualization and then extend virtualization into arenas such as the desktop while continuing to address traditional database workloads, storage must handle multiple requirements equally well. Disk can’t do it anymore. Flash can.
First, we must move beyond the concept that we implement storage solutions to solve individual application requirements. Instead, at every opportunity data center managers should be architecting and then implementing storage solutions capable of addressing multiple storage requirements. And even more, such a comprehensive storage solution must be cost effective when we buy it, yet possess additional capabilities that will enable both future growth and new business initiatives.
Certain flash products are a very good choice as do-more storage solutions. Others, not so much. Virtual Desktop Infrastructure (VDI) and inline deduplication offer insights into why IBM FlashSystem makes a very good choice to fill the multi-tasking role in your storage architecture.
Consider VDI. VDI seeks to eliminate hundreds to thousands of difficult to upgrade, manage, and secure desktops with a consolidated set of centralized servers and storage that are in turn easier to upgrade, manage, and secure. But here’s the key ingredient of a smarter data center: The infrastructure used to support VDI must be able to do more than implement VDI. The VDI workload has very high I/O density. While the I/O of a single physical desktop is easily handled with a fast HDD or small SSD, consolidating all of these desktops into a VDI creates extremely high I/O demands that are difficult to meet with typical hybrid SAN storage arrays. Principal causes of failed VDI installations include the costs and complexities of implementing storage to support it. A simplistic way to solve the problem is to buy an HDD or SSD for every virtualized desktop. This is expensive and inefficient, resulting in almost no practical cost savings versus the storage already in the desktop.
It turns out that VDI workloads benefit from inline deduplication. Whether the VDI is persistent or stateless, inline deduplication often results in a nearly 10x reduction in storage capacity needed. Inline deduplication works so well in VDI environments because the images needed for each virtual desktop are largely the same across desktops. Additionally, inline deduplication is effective at decreasing the capacity needed to store the unstructured files generated most often in a typical desktop environment.
Inline deduplication is essential to reducing the cost of large scale VDI. Inline deduplication, however, has a dark side: it dramatically increases the I/O density for VDI, making traditional storage arrays an incredibly poor choice for VDI. Before inline deduplication, the I/O density of VDI was not substantially different from the I/O density of the actual desktop.
Flash appliances are the best solution for handling the I/O density created by inline deduplication with VDI. Flash appliances are optimized for high I/O density workloads and bring an added benefit in that they tend to decrease the latency for data access, meaning the end user experience with flash as the storage media is likely to be even better than if users were getting data from a disk drive inside their desktop.
Data center managers have a choice to make: choose a storage architecture that creates an application silo or choose a storage architecture that can support multiple performance sensitive use cases. In fact, VDI is not the only application that benefits from flash appliances. The number one application for flash appliances is database acceleration. It is beneficial for the data center manager to pick a flash appliance that can truly multi-task, handling VDI workloads and database workloads with equal effectiveness. But, the capability to handle high I/O density is the number one requirement for VDI workloads, whereas extremely low latency is the number one requirement for database workloads.
At this point, the field of potential do-everything solutions narrows quickly. It just so happens that flash appliances with built-in deduplication are the worst choices for database acceleration. The inline deduplication that provides significant benefits for VDI provides almost no data reduction benefits for databases; instead the very process of deduplicating data is latency inducing, thus degrading database performance. For this reason, IBM with its FlashSystem appliance does not implement full-time, can’t be turned off, inline deduplication. This would be contrary to the trajectory of the data center toward virtualization, decreased silos, and ultimately storage solutions that do everything well.
In this way, IBM covers all the bases. FlashSystem offers the low latency, extreme performance, high availability, and fat bandwidth to serve very well as the foundational multi-tasking storage. Then, IBM offers a variety of ways that solutions for specific application requirements can easily be layered over the FlashSystem foundation. For example, IBM partners with Atlantis Computing to provide a best-of-breed solution for VDI. Atlantis Computing ILIO software executes within a virtual machine (VM), thus it does not require a server silo and provides compression and deduplication capabilities explicitly designed for VDI. A single FlashSystem appliance can serve up over one thousand volumes from its 40TB of protected capacity. The appropriate capacity is allocated for use with VDI and provides the I/O density and low latency that reduce the cost per desktop of VDI while improving the end user experience. Because even very large VDI implementations do not use 40TB of capacity, the remaining capacity of the IBM FlashSystem can be allocated to accelerating databases.
As the data center footprint of flash expands, FlashSystem is uniquely capable of supporting every workload with equal efficiency. With the economics of flash already past the tipping point, data center managers should be looking at long term strategies for replacing performance HDD with flash appliances. Creating silos that only handle a single storage challenge such as VDI will waste multiple opportunities to increase overall data center storage performance and efficiency while at the same time lowering storage costs. Implementing smarter, highly capable FlashSystem storage enables data center managers to address multiple storage challenges today, while empowering growth and innovation in the future.
Learn more about using flash to handle multiple workloads at the upcoming Flash Memory Summit in Santa Clara and VMworld in San Francisco! I will be at both events and hope to see you there. To learn more about the work IBM is doing with Atlantis Computing, please visit the IBM FlashSystem EcoSystem website.