A recent article from CIO magazine talks about managing the flow of real-time data. The VC in Vacation Land also references this article in his series on real-time data. While real-time is usually thought of as a good thing, it can lead to problems if it is misused. The article cites studies that show that often managers make worse decisions when they have access to real-time information. Here are some of the reasons:

• Information overload - people can only handle so much data before it usefulness deteriorates
• Trust - if you get 100 alerts a day, you're going to start tuning them out (anyone who has started using Windows Vista will understand this)
• Spikes - an exception condition can look like a trend when seen over a very short time horizon
• Bad data - it's difficult enough to synchronize data among multiple systems, but having bad real-time data will be much more challenging to analyze and fix due to the volume.

So is having real-time data a bad thing? No, but it must be used appropriately. Some ideas:

• Segment metrics into those that should or should not be viewed real-time. For example, overall demand information is probably too susceptible to spikes to warrant viewing it real-time, while tracking individual orders may benefit.
• Provide real-time data to the appropriate people or roles. Generally speaking (there are exceptions), the higher up in the management structure, the less real-time the data needs to be.
• Make sure alerts are displayed only when they are truly actionable. Build in tolerances that will cause an exception to be ignored if it is transient. Conversely, you may want to report the spikes in an aggregate, less real-time way in order to analyze why they are occurring.
• Understand the costs of extracting real-time data in terms of the load on both the monitoring application and the back-end or legacy systems. In a perfect world, all data could be real-time and rolled up to the best time period, but the reality is that there is a performance hit so determine up front just how real-time the data needs to be and only extract it as needed.