Cost of downtime
Sunday, March 14, 2010
4:45 PM
Patterson's equation: 
Downtime (unavailability) has a tangible business cost. 
Cost of downtime 
= (average revenue lost/hour) * downtime hours 
+ (average work lost/hour) * downtime hours. 
work lost: things that don't get done while you are paying staff to do them. 
revenue lost: sales are not made because resources are not available.
Sources: 
Patterson, "A simple model of the cost of downtime", Proc. LISA 2002. 
Couch et al, "Toward a cost model for system administration", Proc. LISA 2005. 