Runtime Events and Metrics Data Model

Events	Description
Lifecycle	A Lifecycle event is generated each time the API Gateway instance is started or shut down.
Error	An Error event is generated each time an invocation of API results in an error.
Policy Violation	A Policy Violation event is generated each time an invocation of API violates a policy that was configured for the API.
Transaction	A Transaction event is generated each time an API is invoked (successfully or unsuccessfully).
Monitor	A Monitor event is generated when a configured SLA parameter, such as the average response time, fault count, availability, and so on, is breached for the API.

KPI metrics are used to monitor the run-time execution of APIs. Metrics include the maximum response time, average response time, fault count, availability of APIs, and so on. If you include runtime monitoring policies, the policies will monitor the KPI metrics for APIs, and can send alerts to various destinations when user-specified performance conditions for an API are violated. The KPI metrics that API Gateway can generate are:

Metric	Reports on...
Availability	The percentage of time that an API was available during the current interval. A value of 100 indicates that the API was always available. Only the time when the API is unavailable counts against this metric. If invocations fail due to policy violations, this parameter could still be as high as 100.
Average Response Time	The average amount of time it took the API to complete all invocations in the current interval. This is measured from the moment API Gateway receives the request until the moment it returns the response to the client.
Fault Count	The number of failed invocations in the current interval.
Maximum Response Time	The maximum amount of time it took the API to complete an invocation in the current interval.
Minimum Response Time	The minimum amount of time it took the API to complete an invocation in the current interval.
Successful Request Count	The number of successful API invocations in the current interval.
Total Request Count	The total number of requests for each API running in API Gateway in the current interval.