# I Want to Know what Availability Means

> What availability means in PerformanceGuard graphs and widgets, and when something counts as available.

Source: https://docs.capaone.com/performanceguard/i-want-to-know/i-want-to-know-what-availability-means/  
Product: PerformanceGuard — a separate CapaSystems product; do not apply this page to any other.

Many PerformanceGuard graphs and widgets—for example the [Application Chart Widget](/performanceguard/dashboards-and-widgets/widgets/application-chart-widget/)—are able to show the availability of applications, servers, etc., but what is availability?

:::note[Important]
<details>
<summary>When is something considered to be available?</summary>

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 *un*available. 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 *un*available, 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.

<details>
<summary>Do you measure availability of application pings (HTTP requests, ICMP ping and/or traceroutes)?</summary>

For **[Monitor Availability, Latency and Response Times with Application Ping](..\Administration\Manage%20Agent%20Configuration%20Groups\Agent%20Configuration%20Group%20Settings\Monitor%20Availability,%20Latency%20and%20Response%20Times%20with%20Application%20Ping.md)**, PerformanceGuard looks not only at acceptable response times, but also at whether a response is expected or not: If the response is unexpected, for example if the response has a response code of *404 Not Found*, PerformanceGuard considers the service to be *un*available, even if the response was received within acceptable time.

</details>

</details>
:::

:::note[Important]
<details>
<summary>How does PerformanceGuard calculate the availability %?</summary>

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

</details>
:::

:::note[Important]
<details>
<summary>I just set up a new server. Nobody has used it yet. How can it be 100% available?</summary>

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 *un*available. Everything that's not *un*available, is considered by PerformanceGuard to be available, and that explains the 100% availability, even though nobody has yet used your new server.

</details>
:::