MemoryCountersMetric

public MemoryCountersMetric(
    @NonNull String processNameSuffix,
    @NonNull String metricNameSuffix
)

public @NonNull List<@NonNull Metric.Measurement> getMeasurements(
    @NonNull Metric.CaptureInfo captureInfo,
    @NonNull TraceProcessor.Session traceSession
)

import androidx.benchmark.macro.ExperimentalMetricApi
import androidx.benchmark.macro.TraceMetric
import androidx.benchmark.traceprocessor.TraceProcessor

/**
 * Calculates latency of sections where begin and end trace points are in different processes.
 *
 * @param beginPointName Name of begin tracepoint.
 * @param endPointName Name of end tracepoint.
 * @param eventName Name of the final metric that is spit out after the test run. The metric
 *   name will be {$eventName}LatencyMillis.
 */
@OptIn(ExperimentalMetricApi::class)
class CrossProcessLatencyMetricSample(
    private val beginPointName: String,
    private val endPointName: String,
    private val eventName: String,
) : TraceMetric() {
    @OptIn(ExperimentalMetricApi::class)
    override fun getMeasurements(
        captureInfo: CaptureInfo,
        traceSession: TraceProcessor.Session,
    ): List<Measurement> {
        val query =
            """
         INCLUDE perfetto module slices.with_context;
         SELECT
             event,
             ts2-ts1 AS latency_in_nanos
         FROM
         (
           (SELECT
               ts AS ts1,
               "event" AS event,
               LOWER(TRIM(process_name)) as process_name_1
               FROM thread_slice WHERE name = '${beginPointName}'
           )
           LEFT JOIN
           (SELECT
               ts AS ts2,
               "event" AS event,
               LOWER(TRIM(process_name)) as process_name_2
               FROM thread_slice WHERE name = '${endPointName}'
           )
           USING (event)
         )
           """
                .trimIndent() // maybe add checks for process name etc too in query

        val rowSequence = traceSession.query(query)
        // First row (or null) is returned.
        val latencyResultNanos = rowSequence.firstOrNull()?.long("latency_in_nanos")
        return if (latencyResultNanos != null) {
            listOf(Measurement(eventName + "LatencyMillis", latencyResultNanos / 1_000_000.0))
        } else {
            emptyList()
        }
    }
}