Set Up Performance

With performance monitoring, 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.

Configure the Sample Rate

Sampling for transactions must also be configured before

1. 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.)
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.

func main() {
	err := sentry.Init(sentry.ClientOptions{
		// ...

		EnableTracing: true,
		// Specify a fixed sample rate:
		// We recommend adjusting this value in production
		TracesSampleRate: 1.0,
		// Or provide a custom sample rate:
		TracesSampler: sentry.TracesSampler(func(ctx sentry.SamplingContext) float64 {
			// As an example, this custom sampler does not send some
			// transactions to Sentry based on their name.
			hub := sentry.GetHubFromContext(ctx.Span.Context())
			name := hub.Scope().Transaction()
			if name == "GET /favicon.ico" {
				return 0.0
			}

			return 1.0
		}),
	})
}

Learn more about how the options work in Sampling Transactions.

Verify

Test out

While you're testing, set TracesSampleRate to 1.0, as that ensures that every transaction will be sent to Sentry.

Once testing is complete, we recommend lowering this value in production by either lowering your TracesSampleRate value, or switching to using TracesSampler to dynamically sample and filter your transactions.

Connecting Services

If you are also using Performance Monitoring for JavaScript, depending on where your request originates, you can connect traces:

1. For requests that start in your backend, by adding a meta tag in your HTML template that contains
   tracingThe process of logging the events that took place during a request, often across multiple services.
   information.
2. For requests that start in JavaScript, by the SDK setting a header on requests to your backend.

Otherwise, backend services with Performance Monitoring connect automatically.

Next Steps: