Until now, the discussion on monitoring has been largely focused on being proactive and reactive in a production environment. However, if you have the proper monitoring, you can use it for much more than your 24- hour operations: you can use it like a crystal ball to help you predict the future.
In numerous places in this book, capacity planning has been mentioned as a success factor in helping you with your solutions. The only way to achieve any reasonable form of capacity planning is with data gathered through monitoring. If you are carefully tracking each systems usage over time, you are actually painting an accurate picture of its life. Much like medical records and family history are leading indicators of an individuals health future, these reports and collected data can help you predict things such as usage, rate of growth, potential bottlenecks, system life cycles, availability potential, and more. Look back at Chapter 4 and Chapter 11, Real-World High Availability Solutions, for planning your disk capacity, where ways to arrive at an intelligent guess based on pure data consumption were discussed. But what if you knew things like how many new users you would add per month or per year? How much better would your guess be if you knew what the trends for index growth and usage patterns were? Some would argue that disk space is cheap and quite available. However, disks become increasingly slower when data is being put close to the spindle. Sizing right in the beginning is another sign of a sophisticated operations team.