Red Hat Summit2.17.4.3. Adjusting the sampling rate
A trace is an execution path between services in the service mesh. A trace is comprised of one or more spans. A span is a logical unit of work that has a name, start time, and duration. The sampling rate determines how often a trace is persisted.
The Envoy proxy sampling rate is set to sample 100% of traces in your service mesh by default. A high sampling rate consumes cluster resources and performance but is useful when debugging issues. Before you deploy Red Hat OpenShift Service Mesh in production, set the value to a smaller proportion of traces. For example, set spec.tracing.sampling to 100 to sample 1% of traces.
Configure the Envoy proxy sampling rate as a scaled integer representing 0.01% increments.
In a basic installation, spec.tracing.sampling is set to 10000, which samples 100% of traces. For example:
- Setting the value to 10 samples 0.1% of traces.
- Setting the value to 500 samples 5% of traces.
The Envoy proxy sampling rate applies for applications that are available to a Service Mesh, and use the Envoy proxy. This sampling rate determines how much data the Envoy proxy collects and tracks.
The Jaeger remote sampling rate applies to applications that are external to the Service Mesh, and do not use the Envoy proxy, such as a database. This sampling rate determines how much data Red Hat OpenShift Distributed Tracing Platform collects and stores.
Procedure
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In the OpenShift Container Platform web console, click Ecosystem
Installed Operators. - Click the Project menu and select the project where you installed the control plane, for example istio-system.
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Click the Red Hat OpenShift Service Mesh Operator. In the Istio Service Mesh Control Plane column, click the name of your
ServiceMeshControlPlaneresource, for examplebasic. To adjust the sampling rate, set a different value for
spec.tracing.sampling.- Click the YAML tab.
Set the value for
spec.tracing.samplingin yourServiceMeshControlPlaneresource. In the following example, set it to100.Jaeger sampling example
spec: tracing: sampling: 100- Click Save.
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Click Reload to verify the
ServiceMeshControlPlaneresource was configured correctly.
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