ddtrace Sampling¶

Prerequisites¶

• Enable the DataKit ddtrace collector

• Prepare Shell

java -javaagent:D:/ddtrace/dd-java-agent-0.114.0.jar \
-Ddd.service.name=ddtrace-server \
-Ddd.agent.port=9529 \
-jar springboot-ddtrace-server.jar

Installation and Deployment¶

1 Sampler Configuration in ddtrace.conf¶

  ## Sampler config uses to set global sampling strategy.
  ## sampling_rate used to set global sampling rate.
  [inputs.ddtrace.sampler]
    sampling_rate = 0.1

2 Test Script¶

for ((i=1;i<=100;i++)); 
do
    curl http://localhost:8080/counter
done

3 Enable Sampling¶

1. Enable Sampling on the Collector Side

The range of sampling_rate is (0,1). If the value is outside this range, the trace is discarded.

If full sampling is required, do not configure [inputs.ddtrace.sampler].

1. Enable Sampling on the Application Side

Enable sampling on the application side by using -Ddd.trace.sample.rate, with the range (0,1).

This is a tagged sampling, meaning the trace is fully collected while a sampling tag is applied.

1. Sampling Priority

Both sampling methods have the same effect. If both are configured, the collector-side sampling does not take effect. That is:

Reference Documentation¶

<Demo Source Code>

<ddtrace Startup Options>