I Want to Know what Availability Means

To answer this we need to look at response times: If response times are so long that use of a service, website, transaction or similar becomes impossible, PerformanceGuard considers the service, etc. to be unavailable. By default, PerformanceGuard loses its patience with a service, etc. if it hasn't responded within 500,000 milliseconds (that's a little more than eight minutes). Everything that's not unavailable, is considered by PerformanceGuard to be available. So, if you see that a service has been 100% available during the last week, it means that it has not exceeded the acceptable response time limit during the last week.

PerformanceGuard looks at the ratio between failed requests and all requests in percent. In other words: (all requests − failed requests) / all requests × 100

Bear in mind that PerformanceGuard looks at your new server based on how the PerformanceGuard agents experience it: If none of the computers with PerformanceGuard agents have used the new server, there have not been any unacceptably long response times, and the server has thus not been unavailable. Everything that's not unavailable, is considered by PerformanceGuard to be available, and that explains the 100% availability, even though nobody has yet used your new server.