---
title: "Tracing"
description: "Learn how to enable tracing in your app and discover valuable performance insights of your application."
url: https://docs.sentry.io/platforms/java/guides/log4j2/tracing/
---

# Set Up Tracing | Sentry for Log4j 2.x

With [tracing](https://docs.sentry.io/product/insights/overview.md), Sentry tracks your software performance, measuring metrics like throughput and latency, and displaying the impact of errors across multiple systems. Sentry captures distributed traces consisting of transactions and spans, which measure individual services and individual operations within those services. Learn more about our model in [Distributed Tracing](https://docs.sentry.io/product/sentry-basics/tracing/distributed-tracing.md).

If you’re adopting Tracing in a high-throughput environment, we recommend testing prior to deployment to ensure that your service’s performance characteristics maintain expectations.

Sentry can integrate with **OpenTelemetry**. You can find more information about it [here](https://docs.sentry.io/platforms/java/guides/log4j2/tracing/instrumentation/opentelemetry.md).

## [Requirements](https://docs.sentry.io/platforms/java/guides/log4j2/tracing.md#requirements)

Tracing is available for the Sentry Java SDK version ≥ 4.0.

## [Configure](https://docs.sentry.io/platforms/java/guides/log4j2/tracing.md#configure)

First, enable tracing and configure the sample rate for transactions. Set the sample rate for your transactions by either:

* Setting a uniform sample rate for all transactions using the `tracesSampleRate` option in your SDK config to a number between `0` and `1`. (For example, to send 20% of transactions, set `tracesSampleRate` to `0.2`.)
* Controlling the sample rate based on the transaction itself and the context in which it's captured, by providing a function to the `tracesSampler` config option.

The two options are meant to be mutually exclusive. If you set both, `tracesSampler` will take precedence.

If you are using either our [Spring](https://docs.sentry.io/platforms/java/guides/spring/performance.md) or [Spring Boot](https://docs.sentry.io/platforms/java/guides/spring-boot/performance.md) integrations, errors are linked with spans automatically.

```java
import io.sentry.Sentry;

Sentry.init(options -> {
    options.setDsn("___PUBLIC_DSN___");

+   // To set a uniform sample rate
+   options.setTracesSampleRate(1.0);

+   // OR if you prefer, determine traces sample rate based on the sampling context
+   options.setTracesSampler(
+     context -> {
+       // return a number between 0 and 1 or null (to fallback to configured value)
+     }
+   );
});
```

Learn more about tracing [options](https://docs.sentry.io/platforms/java/guides/log4j2/configuration/options.md#tracing-options), how to use the [tracesSampler](https://docs.sentry.io/platforms/java/guides/log4j2/configuration/sampling.md#setting-a-sampling-function) function, or how to [sample transactions](https://docs.sentry.io/platforms/java/guides/log4j2/configuration/sampling.md#sampling-transaction-events).

## [Verify](https://docs.sentry.io/platforms/java/guides/log4j2/tracing.md#verify)

While you're testing, set `tracesSampleRate` to `1.0`, as that ensures that every transaction will be sent to Sentry. Once testing is complete, you may want to set a lower `tracesSampleRate` value, or switch to using `tracesSampler` to selectively sample and filter your transactions, based on contextual data.

## [Next Steps](https://docs.sentry.io/platforms/java/guides/log4j2/tracing.md#next-steps)

* #### [Instrumentation](https://docs.sentry.io/platforms/java/guides/log4j2/tracing/instrumentation.md)

  Learn how to instrument tracing in your app.

* #### [Trace Propagation](https://docs.sentry.io/platforms/java/guides/log4j2/tracing/trace-propagation.md)

  Learn how to connect events across applications/services.

* #### [Troubleshooting](https://docs.sentry.io/platforms/java/guides/log4j2/tracing/troubleshooting.md)

  Learn how to troubleshoot your tracing setup.

## Pages in this section

- [Instrumentation](https://docs.sentry.io/platforms/java/guides/log4j2/tracing/instrumentation.md)
- [Trace Propagation](https://docs.sentry.io/platforms/java/guides/log4j2/tracing/trace-propagation.md)
- [Troubleshooting](https://docs.sentry.io/platforms/java/guides/log4j2/tracing/troubleshooting.md)