TraceMetric
@ExperimentalMetricApi
public abstract class TraceMetric extends Metric
MemoryCountersMetric | Captures the number of page faults over time for a target package name. |
MemoryUsageMetric | Metric for tracking the memory usage of the target application. |
Metric which captures results from a Perfetto trace with custom TraceProcessor queries.
This is a more customizable version of TraceSectionMetric which can perform arbitrary queries against the captured PerfettoTrace.
Sample metric which finds the duration of the first "activityResume" trace section for the traced package:
class ActivityResumeMetric : TraceMetric() {
override fun getMeasurements(
captureInfo: CaptureInfo,
traceSession: TraceProcessor.Session
): List<Measurement> {
val rowSequence = traceSession.query(
"""
SELECT
slice.name as name,
slice.ts as ts,
slice.dur as dur
FROM slice
INNER JOIN thread_track on slice.track_id = thread_track.id
INNER JOIN thread USING(utid)
INNER JOIN process USING(upid)
WHERE
process.name LIKE ${captureInfo.targetPackageName}
AND slice.name LIKE "activityResume"
""".trimIndent()
)
// this metric queries a single slice type to produce submetrics, but could be extended
// to capture timing of every component of activity lifecycle
val activityResultNs = rowSequence.firstOrNull()?.double("dur")
return if (activityResultMs != null) {
listOf(Measurement("activityResumeMs", activityResultNs / 1_000_000.0))
} else {
emptyList()
}
}
}
| See also | |
|---|---|
TraceProcessor | |
TraceProcessor.Session | |
query |
Summary
Public constructors |
|---|
Public methods | |
|---|---|
abstract @NonNull List<@NonNull Metric.Measurement> | getMeasurements(Get the metric result for a given iteration given information about the target process and a TraceProcessor session |
Public constructors
Public methods
getMeasurements
Added in 1.4.0
public abstract @NonNull List<@NonNull Metric.Measurement> getMeasurements(
@NonNull Metric.CaptureInfo captureInfo,
@NonNull TraceProcessor.Session traceSession
)
Get the metric result for a given iteration given information about the target process and a TraceProcessor session
import androidx.benchmark.macro.ExperimentalMetricApi import androidx.benchmark.macro.TraceMetric import androidx.benchmark.traceprocessor.TraceProcessor /** * Calculates latency of sections where begin and end trace points are in different processes. * * @param beginPointName Name of begin tracepoint. * @param endPointName Name of end tracepoint. * @param eventName Name of the final metric that is spit out after the test run. The metric * name will be {$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() } } }