Performance Metrics
Learn how to attach performance metrics to your transactions.
Sentry's SDKs support sending performance metrics data to Sentry. These are numeric values attached to transactions that are aggregated and displayed in Sentry.
If configured, the React Native SDK automatically collects the following performance metrics:
In addition to automatic performance metrics, the SDK supports setting custom performance metrics on transactions. This allows you to define metrics that are important to your application and send them to Sentry.
To set a performance metric, you need to supply the following:
- name (
string
) - value (any numeric type -
float
,integer
, etc.) - unit (
string
, Defaults to the stringnone
if omitted.)
Sentry supports adding arbitrary custom units, but we recommend using one of the supported units listed below.
Adding custom metrics is supported in Sentry's React Native SDK version 4.0.0
and above.
import * as Sentry from "@sentry/react-native";
const transaction = Sentry.getCurrentScope().getTransaction();
// Record amount of memory used
transaction.setMeasurement("memoryUsed", 123, "byte");
// Record time when Footer component renders on page
transaction.setMeasurement("ui.footerComponent.render", 1.3, "second");
// Record amount of times localStorage was read
transaction.setMeasurement("localStorageRead", 4);
Currently, unit conversion is only supported once the data has already been stored. This means that, for example, ('myMetric', 60, 'second')
and ('myMetric', 3, 'minute')
would not be aggregated, but rather stored as two separate metrics. To avoid this, make sure to use a consistent unit when recording a custom metric.
Units augment metric values by giving meaning to what otherwise might be abstract numbers. Adding units also allows Sentry to offer controls - unit conversions, filters, and so on - based on those units. For values that are unitless, you can supply an empty string or none
.
nanosecond
microsecond
millisecond
second
minute
hour
day
week
bit
byte
kilobyte
kibibyte
megabyte
mebibyte
gigabyte
gibibyte
terabyte
tebibyte
petabyte
pebibyte
exabyte
exbibyte
ratio
percent
If you want to explore further, you can find details about supported units in our event ingestion documentation.
Our documentation is open source and available on GitHub. Your contributions are welcome, whether fixing a typo (drat!) or suggesting an update ("yeah, this would be better").