mirror of
https://codeberg.org/superseriousbusiness/gotosocial.git
synced 2024-12-30 12:58:16 +03:00
81 lines
2.8 KiB
Go
81 lines
2.8 KiB
Go
// Copyright The OpenTelemetry Authors
|
|
// SPDX-License-Identifier: Apache-2.0
|
|
|
|
package metric // import "go.opentelemetry.io/otel/sdk/metric"
|
|
|
|
import (
|
|
"os"
|
|
"runtime"
|
|
"slices"
|
|
|
|
"go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
|
|
"go.opentelemetry.io/otel/sdk/metric/internal/x"
|
|
)
|
|
|
|
// reservoirFunc returns the appropriately configured exemplar reservoir
|
|
// creation func based on the passed InstrumentKind and user defined
|
|
// environment variables.
|
|
//
|
|
// Note: This will only return non-nil values when the experimental exemplar
|
|
// feature is enabled and the OTEL_METRICS_EXEMPLAR_FILTER environment variable
|
|
// is not set to always_off.
|
|
func reservoirFunc[N int64 | float64](agg Aggregation) func() exemplar.FilteredReservoir[N] {
|
|
if !x.Exemplars.Enabled() {
|
|
return nil
|
|
}
|
|
// https://github.com/open-telemetry/opentelemetry-specification/blob/d4b241f451674e8f611bb589477680341006ad2b/specification/configuration/sdk-environment-variables.md#exemplar
|
|
const filterEnvKey = "OTEL_METRICS_EXEMPLAR_FILTER"
|
|
|
|
var filter exemplar.Filter
|
|
|
|
switch os.Getenv(filterEnvKey) {
|
|
case "always_on":
|
|
filter = exemplar.AlwaysOnFilter
|
|
case "always_off":
|
|
return exemplar.Drop
|
|
case "trace_based":
|
|
fallthrough
|
|
default:
|
|
filter = exemplar.SampledFilter
|
|
}
|
|
|
|
// https://github.com/open-telemetry/opentelemetry-specification/blob/d4b241f451674e8f611bb589477680341006ad2b/specification/metrics/sdk.md#exemplar-defaults
|
|
// Explicit bucket histogram aggregation with more than 1 bucket will
|
|
// use AlignedHistogramBucketExemplarReservoir.
|
|
a, ok := agg.(AggregationExplicitBucketHistogram)
|
|
if ok && len(a.Boundaries) > 0 {
|
|
cp := slices.Clone(a.Boundaries)
|
|
return func() exemplar.FilteredReservoir[N] {
|
|
bounds := cp
|
|
return exemplar.NewFilteredReservoir[N](filter, exemplar.Histogram(bounds))
|
|
}
|
|
}
|
|
|
|
var n int
|
|
if a, ok := agg.(AggregationBase2ExponentialHistogram); ok {
|
|
// Base2 Exponential Histogram Aggregation SHOULD use a
|
|
// SimpleFixedSizeExemplarReservoir with a reservoir equal to the
|
|
// smaller of the maximum number of buckets configured on the
|
|
// aggregation or twenty (e.g. min(20, max_buckets)).
|
|
n = int(a.MaxSize)
|
|
if n > 20 {
|
|
n = 20
|
|
}
|
|
} else {
|
|
// https://github.com/open-telemetry/opentelemetry-specification/blob/e94af89e3d0c01de30127a0f423e912f6cda7bed/specification/metrics/sdk.md#simplefixedsizeexemplarreservoir
|
|
// This Exemplar reservoir MAY take a configuration parameter for
|
|
// the size of the reservoir. If no size configuration is
|
|
// provided, the default size MAY be the number of possible
|
|
// concurrent threads (e.g. number of CPUs) to help reduce
|
|
// contention. Otherwise, a default size of 1 SHOULD be used.
|
|
n = runtime.NumCPU()
|
|
if n < 1 {
|
|
// Should never be the case, but be defensive.
|
|
n = 1
|
|
}
|
|
}
|
|
|
|
return func() exemplar.FilteredReservoir[N] {
|
|
return exemplar.NewFilteredReservoir[N](filter, exemplar.FixedSize(n))
|
|
}
|
|
}
|