io.opentelemetry.sdk.metrics.internal.view.Base2ExponentialHistogramAggregation Maven / Gradle / Ivy
/*
* Copyright The OpenTelemetry Authors
* SPDX-License-Identifier: Apache-2.0
*/
package io.opentelemetry.sdk.metrics.internal.view;
import static io.opentelemetry.api.internal.Utils.checkArgument;
import io.opentelemetry.sdk.common.Clock;
import io.opentelemetry.sdk.internal.RandomSupplier;
import io.opentelemetry.sdk.metrics.Aggregation;
import io.opentelemetry.sdk.metrics.data.ExemplarData;
import io.opentelemetry.sdk.metrics.data.MetricDataType;
import io.opentelemetry.sdk.metrics.data.PointData;
import io.opentelemetry.sdk.metrics.internal.aggregator.Aggregator;
import io.opentelemetry.sdk.metrics.internal.aggregator.AggregatorFactory;
import io.opentelemetry.sdk.metrics.internal.aggregator.DoubleBase2ExponentialHistogramAggregator;
import io.opentelemetry.sdk.metrics.internal.descriptor.InstrumentDescriptor;
import io.opentelemetry.sdk.metrics.internal.exemplar.ExemplarFilter;
import io.opentelemetry.sdk.metrics.internal.exemplar.ExemplarReservoir;
/**
* Exponential bucket histogram aggregation configuration.
*
* This class is internal and is hence not for public use. Its APIs are unstable and can change
* at any time.
*/
public final class Base2ExponentialHistogramAggregation implements Aggregation, AggregatorFactory {
private static final int DEFAULT_MAX_BUCKETS = 160;
private static final int DEFAULT_MAX_SCALE = 20;
private static final Aggregation DEFAULT =
new Base2ExponentialHistogramAggregation(DEFAULT_MAX_BUCKETS, DEFAULT_MAX_SCALE);
private final int maxBuckets;
private final int maxScale;
private Base2ExponentialHistogramAggregation(int maxBuckets, int maxScale) {
this.maxBuckets = maxBuckets;
this.maxScale = maxScale;
}
public static Aggregation getDefault() {
return DEFAULT;
}
/**
* Aggregations measurements into an {@link MetricDataType#EXPONENTIAL_HISTOGRAM}.
*
* @param maxBuckets the max number of positive buckets and negative buckets (max total buckets is
* 2 * {@code maxBuckets} + 1 zero bucket).
* @param maxScale the maximum and initial scale. If measurements can't fit in a particular scale
* given the {@code maxBuckets}, the scale is reduced until the measurements can be
* accommodated. Setting maxScale may reduce the number of downscales. Additionally, the
* performance of computing bucket index is improved when scale is <= 0.
* @return the aggregation
*/
public static Aggregation create(int maxBuckets, int maxScale) {
checkArgument(maxBuckets >= 1, "maxBuckets must be > 0");
checkArgument(maxScale <= 20 && maxScale >= -10, "maxScale must be -10 <= x <= 20");
return new Base2ExponentialHistogramAggregation(maxBuckets, maxScale);
}
@Override
@SuppressWarnings("unchecked")
public Aggregator createAggregator(
InstrumentDescriptor instrumentDescriptor, ExemplarFilter exemplarFilter) {
return (Aggregator)
new DoubleBase2ExponentialHistogramAggregator(
() ->
ExemplarReservoir.filtered(
exemplarFilter,
ExemplarReservoir.doubleFixedSizeReservoir(
Clock.getDefault(),
Runtime.getRuntime().availableProcessors(),
RandomSupplier.platformDefault())),
maxBuckets,
maxScale);
}
@Override
public boolean isCompatibleWithInstrument(InstrumentDescriptor instrumentDescriptor) {
switch (instrumentDescriptor.getType()) {
case COUNTER:
case HISTOGRAM:
return true;
default:
return false;
}
}
@Override
public String toString() {
return "Base2ExponentialHistogramAggregation{maxBuckets="
+ maxBuckets
+ ",maxScale="
+ maxScale
+ "}";
}
}