vendor: update docker/go-metrics v0.0.1

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This commit is contained in:
Sebastiaan van Stijn 2020-01-08 18:27:59 +01:00
parent 6b972e50fe
commit 98dcc5195e
No known key found for this signature in database
GPG key ID: 76698F39D527CE8C
216 changed files with 25458 additions and 3611 deletions

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@ -77,15 +77,20 @@ func NewHighBiased(epsilon float64) *Stream {
// is guaranteed to be within (Quantile±Epsilon).
//
// See http://www.cs.rutgers.edu/~muthu/bquant.pdf for time, space, and error properties.
func NewTargeted(targets map[float64]float64) *Stream {
func NewTargeted(targetMap map[float64]float64) *Stream {
// Convert map to slice to avoid slow iterations on a map.
// ƒ is called on the hot path, so converting the map to a slice
// beforehand results in significant CPU savings.
targets := targetMapToSlice(targetMap)
ƒ := func(s *stream, r float64) float64 {
var m = math.MaxFloat64
var f float64
for quantile, epsilon := range targets {
if quantile*s.n <= r {
f = (2 * epsilon * r) / quantile
for _, t := range targets {
if t.quantile*s.n <= r {
f = (2 * t.epsilon * r) / t.quantile
} else {
f = (2 * epsilon * (s.n - r)) / (1 - quantile)
f = (2 * t.epsilon * (s.n - r)) / (1 - t.quantile)
}
if f < m {
m = f
@ -96,6 +101,25 @@ func NewTargeted(targets map[float64]float64) *Stream {
return newStream(ƒ)
}
type target struct {
quantile float64
epsilon float64
}
func targetMapToSlice(targetMap map[float64]float64) []target {
targets := make([]target, 0, len(targetMap))
for quantile, epsilon := range targetMap {
t := target{
quantile: quantile,
epsilon: epsilon,
}
targets = append(targets, t)
}
return targets
}
// Stream computes quantiles for a stream of float64s. It is not thread-safe by
// design. Take care when using across multiple goroutines.
type Stream struct {