Measuring IT resources across different types of resources, including multiple tiers, categories, types, functions, and cost (price bands) of servers, storage, and networking technologies, is not a trivial task. However, IT resource metrics can be addressed over time to address performance, availability, capacity, and energy to achieve a given level of work or service delivered under different conditions.
It is important to avoid trying to do too much with a single or limited metric that compares too many different facets of resource usage. For example, simply comparing all IT equipment from an inactive, idle perspective does not reflect productivity and energy efficiency for doing useful work. Likewise, not considering low-power modes ignores energy-saving opportunities during low-activity periods. Focusing only on storage or server utilization or capacity per given footprint does not tell how much useful work can be done in that footprint per unit of energy at a given cost and service delivery level.
Virtual data centers require physical resources to function efficiently and in a green or environmentally friendly manner. Thus it is vital to understand the value of resource performance, availability, capacity, and energy usage to deliver various IT services. Understanding the relationship between different resources and how they are used is important to gauge improvement and productivity as well as data center efficiency. For example, while the cost per raw terabyte may seem relatively inexpensive, the cost for I/O response time performance needs to be considered for active data.
Having enough resources to support business and application needs is essential to a resilient storage network. Without adequate storage and storage networking resources, availability and performance can be negatively impacted. Poor metrics and information can lead to poor decisions and management. Establish availability, performance, response time, and other objectives to gauge and measure performance of the end-to-end storage and storage networking infrastructure. Be practical, as it can be easy to get caught up in the details and lose sight of the bigger picture and objectives.
Greg Schulz is the founder of StorageIO, an IT industry research and consulting firm. He has worked as a programmer, systems administrator, disaster recovery consultant, and capacity planner for various IT organizations, and also has held positions with industry vendors. He is author of the new book The Green and Virtual Data Center (CRC) and of the SNIA-endorsed book Resilient Storage Networks (Elsevier).InformationWeek Analytics has published an independent analysis of green IT strategies. Download the report here (registration required).