CfnSamplingRule

Use the `AWS::XRay::SamplingRule` resource to specify a sampling rule, which controls sampling behavior for instrumented applications. Include a `SamplingRule` entity to create or update a sampling rule. > `SamplingRule.Version` can only be set when creating a sampling rule. Updating the version will cause the update to fail. Services retrieve rules with [GetSamplingRules](https://docs.aws.amazon.com//xray/latest/api/API_GetSamplingRules.html) , and evaluate each rule in ascending order of *priority* for each request. If a rule matches, the service records a trace, borrowing it from the reservoir size. After 10 seconds, the service reports back to X-Ray with [GetSamplingTargets](https://docs.aws.amazon.com//xray/latest/api/API_GetSamplingTargets.html) to get updated versions of each in-use rule. The updated rule contains a trace quota that the service can use instead of borrowing from the reservoir.