I’m trying to set the sampling probability for GCP tracing to 100% but the property seems to have no effect, only about 0.1% of all requests appear in the GCP Trace Explorer. All Request get a traceId assigned and 100% of all requests with header X-B3-Sampled=1 appear in the Trace Explorer.

I tried to set management.tracing.sampling.probability=1.0 to have all requests traced, but that property seems to have no effect.

Could anyone please help with that and advise, how to correctly set the sampling rate?

Our setup:

• Spring Boot 3.2.6 (downgraded from 3.3.0 because of https://github.com/GoogleCloudPlatform/spring-cloud-gcp/issues/2917)
• Micrometer for observability
• spring-cloud-gcp 5.4.3

Part of our pom.xml:

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>3.2.6</version>
    <relativePath/>
</parent>
<dependency>
    <groupId>com.google.cloud</groupId>
    <artifactId>spring-cloud-gcp-dependencies</artifactId>
    <version>5.4.3</version>
    <type>pom</type>
    <scope>import</scope>
</dependency>
<dependency>
    <groupId>com.google.cloud</groupId>
    <artifactId>spring-cloud-gcp-starter-logging</artifactId>
    <exclusions>
        <exclusion>
            <groupId>commons-logging</groupId>
            <artifactId>commons-logging</artifactId>
        </exclusion>
    </exclusions>
</dependency>
<dependency>
    <groupId>com.google.cloud</groupId>
    <artifactId>spring-cloud-gcp-starter-trace</artifactId>
    <exclusions>
        <exclusion>
            <groupId>com.google.j2objc</groupId>
            <artifactId>j2objc-annotations</artifactId>
        </exclusion>
        <exclusion>
            <groupId>com.google.errorprone</groupId>
            <artifactId>error_prone_annotations</artifactId>
        </exclusion>
    </exclusions>
</dependency>
<dependency>
    <groupId>io.micrometer</groupId>
    <artifactId>micrometer-registry-prometheus</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-config</artifactId>
</dependency>

Part of our application.yaml:

management:
  tracing:
    sampling:
      probability: 1.0
    enabled: true