One of the most prevalent trends in IT today is server consolidation. Companies consolidate mainly to end server sprawl, reduce total cost of ownership (TCO), increase hardware utilization, and streamline IT resources. But many organizations aren't seeing these benefits. Their different departments and branch offices continually acquire software solutions, which tend to come bundled with server hardware. As these single-purpose servers accumulate, they increase the organizations' operating costs both in terms of direct hardware purchases and maintenance.

In addition to costs, these accumulated servers also increase infrastructure requirements with their power, cooling, and networking demands. Not surprisingly—considering the massive increases in the computing power of today's multicore servers—these single-purpose systems tend to have utilization rates under 20 percent. More systems mean greater management efforts and reduced efficiency and flexibility.

Will Your Organization Benefit From Consolidation?

One well-known management adage sums up this situation: "Every penny spent on hardware requires a dollar to manage." Whether your organization will benefit from consolidation depends on the type of server system you have. Before you jump on the server-consolidation bandwagon, make sure your system is a good candidate for this popular solution.

By definition, server consolidation utilizes a shared hardware environment, and excessive system requirements by one or more of the servers involved will reduce the responsiveness of all of the servers on the platform. Workloads that are best suited for server consolidation have low levels of both CPU and disk resource utilization with occasional spikes of activity where the utilization rate could approach 100 percent for short periods of time. Combining several of these low-level workloads can be advantageous, because they don't tend to overload the target server. When combined together, they can increase server-utilization rates while still maintaining acceptable service levels.

Relational database servers like SQL Server don't always fit into this mold. SQL Server systems often support multiple databases and must concurrently process multiple complex queries—requiring sustained high levels of CPU and memory utilization as well as high I/O requirements. In addition, because many of the applications supported by SQL Server databases are mission critical, the system must also provide high levels of responsiveness, which isn't well suited for server consolidation.

While it's true that many SQL Server installations have the high-system requirements that would cause them to play poorly in a server-consolidation environment, not all SQL Server systems are like that. Many SQL Server systems, especially small departmental and branch-office database servers, have modest requirements.

Boils Down to Characteristics of Your System's Workload

In the end, it all boils down to the characteristics of your system's workload. Workloads with sustained rates of high resource utilization either CPU or I/O aren't good candidates for consolidation. There are many products available like Microsoft Operations Manager (MOM), other third-party performance tools, and even just plain, old Performance Monitor that help you understand your SQL Server system's workload characteristics. Once you learn your system's workload characteristics, you'll know if server consolidation is right for your organization.