
Comparing Storage Energy Efficiency and Effectiveness 245
Four different storage systems are shown in Figure 8.10, each with a
similar number of the same type of high-performance HDDs performing a
transaction-oriented workload. It is important to look at all the available
metrics, particularly for active data storage, to see how much storage capac-
ity will be achieved with a given density, how much power will be needed,
and what level of performance will be provided, considering the total power
footprint as well as the activity per energy used or IOPS per watt.
Look beyond the number of disk drives, the size or amount of cache,
the number and speed of ...