A distributed execution environment provides instances of computing resources for customer use, such as instances of data processing resources, data storage resources, database resources, and networking resources. Data is collected from systems internal to and external to the distributed execution environment. Some or all of the data is utilized to compute instance availability information for instances of computing resources provided by the distributed execution environment. The instance availability information might then be provided to customers and other users of the distributed execution environment. Various types of actions might be taken in a manual or automated way based upon the computed instance availability information.