Set Up
If you’re on a legacy plan, you'll need to add transaction events to your subscription to use performance monitoring.
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.
If you’re adopting Performance in a high-throughput environment, we recommend testing prior to deployment to ensure that your service’s performance characteristics maintain expectations.
Configure the Sample Rate
Once you configure the sample rate, tracing will be enabled in your app. Set the sample rate for your transactions by either:
- Setting a uniform sample rate for all transactions using the
traces_sample_rateoption in your SDK config to a number between0and1. (For example, to send 20% of transactions, settraces_sample_rateto0.2.) - Controlling the sample rate based on the transaction itself and the context in which it's captured, by providing a function to the
traces_samplerconfig option.
The two options are meant to be mutually exclusive. If you set both, traces_sampler will take precedence.
Performance Monitoring is available for the Sentry Python SDK version ≥ 0.11.2.
import sentry_sdk
def traces_sampler(sampling_context):
# ...
# return a number between 0 and 1 or a boolean
sentry_sdk.init(
dsn="https://examplePublicKey@o0.ingest.sentry.io/0",
# To set a uniform sample rate
traces_sample_rate=0.2,
# Alternatively, to control sampling dynamically
traces_sampler=traces_sampler
)Learn more about how the options work in Sampling Transactions.
Verify
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, we recommend lowering this value in production by either lowering your traces_sample_rate value, or switching to using traces_sampler 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:
- For requests that start in your backend, by adding a meta tag in your HTML template that contains tracing information.
- 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: