---
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/rust/guides/axum/tracing/
---

# Set Up Tracing | Sentry for axum

With [tracing](https://docs.sentry.io/product/insights.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.

## [Configure](https://docs.sentry.io/platforms/rust/guides/axum/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 `traces_sample_rate` option in your SDK config to a number between `0` and `1`. (For example, to send 20% of transactions, set `traces_sample_rate` 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 `traces_sampler` config option.

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

```rust
let _guard = sentry::init(sentry::ClientOptions {
    release: sentry::release_name!(),
    // To set a uniform sample rate
    traces_sample_rate: 0.2,
    // The Rust SDK does not currently support `traces_sampler`

    ..Default::default()
});
```

Learn more about tracing [options](https://docs.sentry.io/platforms/rust/guides/axum/configuration/options.md#tracing-options), or how to [sample transactions](https://docs.sentry.io/platforms/rust/guides/axum/configuration/sampling.md#sampling-transaction-events).

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

Verify that tracing is working correctly by using our [automatic instrumentation](https://docs.sentry.io/platforms/rust/guides/axum/tracing/instrumentation/automatic-instrumentation.md) or by starting and finishing a transaction using [custom instrumentation](https://docs.sentry.io/platforms/rust/guides/axum/tracing/instrumentation/custom-instrumentation.md).

While you're testing, set `traces_sample_rate` 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 `traces_sample_rate` value, or switch to using `traces_sampler` to selectively sample and filter your transactions, based on contextual data.

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

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

  Learn how to instrument tracing in your app.

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

  Learn how to connect events across applications/services.

## Pages in this section

- [Instrumentation](https://docs.sentry.io/platforms/rust/guides/axum/tracing/instrumentation.md)
- [Trace Propagation](https://docs.sentry.io/platforms/rust/guides/axum/tracing/trace-propagation.md)