Performance Metrics

Sentry's SDKs support sending performance metrics data to Sentry. These are numeric values attached to transactions that are aggregated and displayed in Sentry.

Custom 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 string none 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 .NET SDK, version 3.23.0 and above.

The following example shows how to set custom metrics on a transaction, including how obtain the current span and get its transaction. If you already have the transaction or span, you can use it directly.

var span = SentrySdk.GetSpan();  // or hub.GetSpan()
if (span != null)
{
    var transaction = span.GetTransaction();

    // Record amount of memory used
    transaction.SetMeasurement("memory_used", 64, MeasurementUnit.Information.Megabyte);

    // Record time it took to load user profile
    transaction.SetMeasurement("user_profile_loading_time", 1.3, MeasurementUnit.Duration.Second);

    // Record number of times the screen was loaded
    transaction.SetMeasurement("screen_load_count", 4);
}

Supported Performance Metric Units

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.

Duration Units

• nanosecond
• microsecond
• millisecond
• second
• minute
• hour
• day
• week

Information Units

• bit
• byte
• kilobyte
• kibibyte
• megabyte
• mebibyte
• gigabyte
• gibibyte
• terabyte
• tebibyte
• petabyte
• pebibyte
• exabyte
• exbibyte

Fraction Units

• ratio
• percent

If you want to explore further, you can find details about supported units in our event ingestion documentation.