forked from TrueCloudLab/hrw
Work around Hashing and tests (#2)
* Work around Hashing and tests * fixes * add TravisCI * fix lint * so slow * add badges * work on README * Improved tests and get rid of fnv (#3)
This commit is contained in:
Evgeniy Kulikov
GitHub
parent
cf9a7e5b89
commit
e5d4b47881
6 changed files with 376 additions and 161 deletions
16
.travis.yml
Normal file
16
.travis.yml
Normal file
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@ -0,0 +1,16 @@
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language: go
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go:
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- 1.11.x
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env:
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- GO111MODULE=on
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install:
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- go get -v golang.org/x/lint/golint
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- go mod tidy -v
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script:
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- golint -set_exit_status ./...
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- go test -race -coverprofile=coverage.txt -covermode=atomic ./...
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after_success:
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- bash <(curl -s https://codecov.io/bash)
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matrix:
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allow_failures:
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- go: tip
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57
README.md
57
README.md
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@ -1 +1,56 @@
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# Golang simple HRW implementation
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# Golang HRW implementation
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[](https://travis-ci.org/im-kulikov/hrw)
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[](https://codecov.io/gh/im-kulikov/hrw)
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[](https://goreportcard.com/report/github.com/im-kulikov/hrw)
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[](https://github.com/im-kulikov/hrw)
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[Rendezvous or highest random weight](https://en.wikipedia.org/wiki/Rendezvous_hashing) (HRW) hashing is an algorithm that allows clients to achieve distributed agreement on a set of k options out of a possible set of n options. A typical application is when clients need to agree on which sites (or proxies) objects are assigned to. When k is 1, it subsumes the goals of consistent hashing, using an entirely different method.
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## Install
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`go get github.com/im-kulikov/hrw`
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## Example
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```go
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package main
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import (
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"fmt"
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"github.com/im-kulikov/hrw"
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)
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func main() {
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// given a set of servers
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servers := []string{
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"one.example.com",
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"two.example.com",
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"three.example.com",
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"four.example.com",
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"five.example.com",
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"six.example.com",
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}
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// HRW can consistently select a uniformly-distributed set of servers for
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// any given key
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var (
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key = []byte("/examples/object-key")
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h = hrw.Hash(key)
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)
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hrw.SortSliceByValue(servers, h)
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for id := range servers {
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fmt.Printf("trying GET %s%s\n", servers[id], key)
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}
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// Output:
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// trying GET four.example.com/examples/object-key
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// trying GET three.example.com/examples/object-key
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// trying GET one.example.com/examples/object-key
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// trying GET two.example.com/examples/object-key
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// trying GET six.example.com/examples/object-key
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// trying GET five.example.com/examples/object-key
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}
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```
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2
go.mod
2
go.mod
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@ -1,3 +1,3 @@
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module github.com/im-kulikov/hrw
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require github.com/reusee/mmh3 v0.0.0-20140820141314-64b85163255b
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require github.com/spaolacci/murmur3 v0.0.0-20180118202830-f09979ecbc72
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4
go.sum
4
go.sum
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@ -1,2 +1,2 @@
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github.com/reusee/mmh3 v0.0.0-20140820141314-64b85163255b h1:GQkEnyBFqzQXb3RFqGt5z2QcBZJVQxgzXKF/sPCFh7w=
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github.com/reusee/mmh3 v0.0.0-20140820141314-64b85163255b/go.mod h1:ADBBIMrt68BC/v967NyoiPZMwPVq44r8QJ5oRyXJHJs=
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github.com/spaolacci/murmur3 v0.0.0-20180118202830-f09979ecbc72 h1:qLC7fQah7D6K1B0ujays3HV9gkFtllcxhzImRR7ArPQ=
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github.com/spaolacci/murmur3 v0.0.0-20180118202830-f09979ecbc72/go.mod h1:JwIasOWyU6f++ZhiEuf87xNszmSA2myDM2Kzu9HwQUA=
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65
hrw.go
65
hrw.go
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@ -3,16 +3,17 @@
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package hrw
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import (
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"errors"
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"hash/fnv"
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"encoding/binary"
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"reflect"
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"sort"
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"strconv"
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"github.com/spaolacci/murmur3"
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)
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type (
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swapper func(i, j int)
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// Hasher interface used by SortSliceByValue
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Hasher interface{ Hash() uint64 }
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hashed struct {
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@ -38,6 +39,12 @@ func (h hashed) Len() int { return h.length }
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func (h hashed) Less(i, j int) bool { return h.weight[h.sorted[i]] < h.weight[h.sorted[j]] }
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func (h hashed) Swap(i, j int) { h.sorted[i], h.sorted[j] = h.sorted[j], h.sorted[i] }
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// Hash uses murmur3 hash to return uint64
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func Hash(key []byte) uint64 {
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return murmur3.Sum64(key)
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}
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// SortByWeight receive nodes and hash, and sort it by weight
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func SortByWeight(nodes []uint64, hash uint64) []uint64 {
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var (
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l = len(nodes)
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@ -57,10 +64,11 @@ func SortByWeight(nodes []uint64, hash uint64) []uint64 {
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return h.sorted
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}
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func SortSliceByValue(slice interface{}, hash uint64) error {
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// SortSliceByValue received []T and hash to sort by value-weight
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func SortSliceByValue(slice interface{}, hash uint64) {
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t := reflect.TypeOf(slice)
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if t.Kind() != reflect.Slice {
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return errors.New("must be slice")
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return
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}
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var (
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@ -71,29 +79,24 @@ func SortSliceByValue(slice interface{}, hash uint64) error {
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)
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if length == 0 {
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return nil
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return
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}
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switch slice := slice.(type) {
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case []int:
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hasher := fnv.New64()
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var key = make([]byte, 16)
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for i := 0; i < length; i++ {
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hasher.Reset()
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// error always nil
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_, _ = hasher.Write([]byte(strconv.Itoa(slice[i])))
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rule = append(rule, weight(hash, hasher.Sum64()))
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binary.BigEndian.PutUint64(key, uint64(slice[i]))
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rule = append(rule, weight(Hash(key), hash))
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}
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case []string:
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hasher := fnv.New64()
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for i := 0; i < length; i++ {
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hasher.Reset()
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// error always nil
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_, _ = hasher.Write([]byte(slice[i]))
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rule = append(rule, weight(hash, hasher.Sum64()))
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rule = append(rule, weight(hash,
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Hash([]byte(slice[i]))))
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}
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default:
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if _, ok := val.Index(0).Interface().(Hasher); !ok {
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return errors.New("unknown type")
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return
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}
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for i := 0; i < length; i++ {
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@ -103,36 +106,44 @@ func SortSliceByValue(slice interface{}, hash uint64) error {
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}
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rule = SortByWeight(rule, hash)
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sortByRule(swap, uint64(length), rule)
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return nil
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sortByRuleInverse(swap, uint64(length), rule)
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}
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// SortSliceByIndex received []T and hash to sort by index-weight
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func SortSliceByIndex(slice interface{}, hash uint64) {
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length := uint64(reflect.ValueOf(slice).Len())
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swap := reflect.Swapper(slice)
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rule := make([]uint64, 0, length)
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for i := uint64(0); i < length; i++ {
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rule = append(rule, i)
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}
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rule = SortByWeight(rule, hash)
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sortByRule(swap, length, rule)
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sortByRuleInverse(swap, length, rule)
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}
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func sortByRule(swap swapper, length uint64, rule []uint64) {
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func sortByRuleDirect(swap swapper, length uint64, rule []uint64) {
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done := make([]bool, length)
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for i := uint64(0); i < length; i++ {
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if done[i] {
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continue
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}
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done[i] = true
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for j := rule[i]; !done[rule[j]]; j = rule[j] {
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swap(int(i), int(j))
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done[j] = true
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}
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}
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}
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func sortByRuleInverse(swap swapper, length uint64, rule []uint64) {
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done := make([]bool, length)
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for i := uint64(0); i < length; i++ {
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if done[i] {
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continue
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}
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for j := i; !done[rule[j]]; j = rule[j] {
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swap(int(j), int(rule[j]))
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done[j] = true
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}
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}
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}
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359
hrw_test.go
359
hrw_test.go
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@ -3,18 +3,15 @@ package hrw
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import (
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"encoding/binary"
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"fmt"
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"hash/fnv"
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"math"
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"reflect"
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"strconv"
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"testing"
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"github.com/reusee/mmh3"
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)
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type hashString string
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var testKey = []byte("Golang simple HRW implementation")
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var testKey = []byte("0xff51afd7ed558ccd")
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func Example() {
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// given a set of servers
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@ -31,64 +28,30 @@ func Example() {
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// any given key
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var (
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key = []byte("/examples/object-key")
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h = hash(key)
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err = SortSliceByValue(servers, h)
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h = Hash(key)
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)
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if err != nil {
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panic(err)
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}
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SortSliceByValue(servers, h)
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for id := range servers {
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fmt.Printf("trying GET %s%s\n", servers[id], key)
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}
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// Output:
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// trying GET six.example.com/examples/object-key
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// trying GET one.example.com/examples/object-key
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// trying GET three.example.com/examples/object-key
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// trying GET four.example.com/examples/object-key
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// trying GET five.example.com/examples/object-key
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// trying GET three.example.com/examples/object-key
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// trying GET one.example.com/examples/object-key
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// trying GET two.example.com/examples/object-key
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// trying GET six.example.com/examples/object-key
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// trying GET five.example.com/examples/object-key
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}
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func (h hashString) Hash() uint64 {
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hs := fnv.New64()
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// error always nil
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_, _ = hs.Write([]byte(h))
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return hs.Sum64() >> 1
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}
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func hash(key []byte) uint64 {
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h := fnv.New64()
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// error always nil
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_, _ = h.Write(key)
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return (h.Sum64() >> 1) ^ math.MaxUint64
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}
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func mur3hash(key []byte) uint64 {
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h := mmh3.New128()
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// error always nil
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_, _ = h.Write(key)
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var (
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data = h.Sum(nil)
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length = len(data)
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result uint64
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)
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for i := 0; i < length; i++ {
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result += uint64(data[i]) << uint64(length-i)
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}
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return result
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return Hash([]byte(h))
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}
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func TestSortSliceByIndex(t *testing.T) {
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actual := []string{"a", "b", "c", "d", "e", "f"}
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expect := []string{"e", "a", "c", "d", "b", "f"}
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hash := hash(testKey)
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expect := []string{"e", "a", "c", "f", "d", "b"}
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hash := Hash(testKey)
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SortSliceByIndex(actual, hash)
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if !reflect.DeepEqual(actual, expect) {
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t.Errorf("Was %#v, but expected %#v", actual, expect)
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@ -97,60 +60,79 @@ func TestSortSliceByIndex(t *testing.T) {
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func TestSortSliceByValue(t *testing.T) {
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actual := []string{"a", "b", "c", "d", "e", "f"}
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expect := []string{"e", "b", "c", "d", "f", "a"}
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hash := hash(testKey)
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if err := SortSliceByValue(actual, hash); err != nil {
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t.Fatal(err)
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}
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expect := []string{"d", "b", "a", "f", "c", "e"}
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hash := Hash(testKey)
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SortSliceByValue(actual, hash)
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if !reflect.DeepEqual(actual, expect) {
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t.Errorf("Was %#v, but expected %#v", actual, expect)
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}
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}
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func TestSortSliceByValueFail(t *testing.T) {
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t.Run("empty slice", func(t *testing.T) {
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actual := make([]int, 0)
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hash := hash(testKey)
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func TestSortByRule(t *testing.T) {
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t.Run("direct", func(t *testing.T) {
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// 0 1 2 3 4 5
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actual := []string{"a", "b", "c", "d", "e", "f"}
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// 4 2 0 5 3 1
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expect := []string{"c", "f", "b", "e", "a", "d"}
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rule := []uint64{4, 2, 0, 5, 3, 1}
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if err := SortSliceByValue(actual, hash); err != nil {
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t.Fatal(err)
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sortByRuleDirect(
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func(i, j int) { actual[i], actual[j] = actual[j], actual[i] },
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6, rule)
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if !reflect.DeepEqual(actual, expect) {
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t.Errorf("Was %#v, but expected %#v", actual, expect)
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}
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})
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t.Run("inverse", func(t *testing.T) {
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// 0 1 2 3 4 5
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actual := []string{"a", "b", "c", "d", "e", "f"}
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// 4 2 0 5 3 1
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expect := []string{"e", "c", "a", "f", "d", "b"}
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rule := []uint64{4, 2, 0, 5, 3, 1}
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sortByRuleInverse(
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func(i, j int) { actual[i], actual[j] = actual[j], actual[i] },
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6, rule)
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|
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if !reflect.DeepEqual(actual, expect) {
|
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t.Errorf("Was %#v, but expected %#v", actual, expect)
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}
|
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})
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}
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func TestSortSliceByValueFail(t *testing.T) {
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t.Run("empty slice", func(t *testing.T) {
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var (
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actual []int
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hash = Hash(testKey)
|
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)
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SortSliceByValue(actual, hash)
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})
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|
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t.Run("must be slice", func(t *testing.T) {
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actual := 10
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hash := hash(testKey)
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if err := SortSliceByValue(actual, hash); err == nil {
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t.Fatal("must fail for bad type")
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}
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|
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hash := Hash(testKey)
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SortSliceByValue(actual, hash)
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})
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|
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t.Run("must fail for unknown type", func(t *testing.T) {
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t.Run("must 'fail' for unknown type", func(t *testing.T) {
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actual := []byte{1, 2, 3, 4, 5}
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hash := hash(testKey)
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if err := SortSliceByValue(actual, hash); err == nil {
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t.Fatal("must fail for bad type")
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expect := []byte{1, 2, 3, 4, 5}
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hash := Hash(testKey)
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SortSliceByValue(actual, hash)
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if !reflect.DeepEqual(actual, expect) {
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t.Errorf("Was %#v, but expected %#v", actual, expect)
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}
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})
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}
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func TestSortSliceByValueHasher(t *testing.T) {
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actual := []hashString{"a", "b", "c", "d", "e", "f"}
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expect := []hashString{"e", "d", "c", "a", "b", "f"}
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hash := hash(testKey)
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if err := SortSliceByValue(actual, hash); err != nil {
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t.Fatal(err)
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}
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|
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expect := []hashString{"d", "b", "a", "f", "c", "e"}
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hash := Hash(testKey)
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SortSliceByValue(actual, hash)
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if !reflect.DeepEqual(actual, expect) {
|
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t.Errorf("Was %#v, but expected %#v", actual, expect)
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}
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|
|
@ -158,14 +140,9 @@ func TestSortSliceByValueHasher(t *testing.T) {
|
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|
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func TestSortSliceByValueIntSlice(t *testing.T) {
|
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actual := []int{0, 1, 2, 3, 4, 5}
|
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expect := []int{2, 0, 5, 3, 4, 1}
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|
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hash := hash(testKey)
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|
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if err := SortSliceByValue(actual, hash); err != nil {
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t.Fatal(err)
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}
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|
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expect := []int{2, 3, 1, 4, 0, 5}
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hash := Hash(testKey)
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SortSliceByValue(actual, hash)
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if !reflect.DeepEqual(actual, expect) {
|
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t.Errorf("Was %#v, but expected %#v", actual, expect)
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}
|
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|
|
@ -173,90 +150,248 @@ func TestSortSliceByValueIntSlice(t *testing.T) {
|
|||
|
||||
func TestSortByWeight(t *testing.T) {
|
||||
nodes := []uint64{1, 2, 3, 4, 5}
|
||||
hash := mur3hash(testKey)
|
||||
|
||||
hash := Hash(testKey)
|
||||
actual := SortByWeight(nodes, hash)
|
||||
expected := []uint64{0, 1, 4, 2, 3}
|
||||
expected := []uint64{3, 1, 4, 2, 0}
|
||||
if !reflect.DeepEqual(actual, expected) {
|
||||
t.Errorf("Was %#v, but expected %#v", actual, expected)
|
||||
}
|
||||
}
|
||||
|
||||
func TestUniformDistribution(t *testing.T) {
|
||||
const (
|
||||
size = 10
|
||||
keys = 100000
|
||||
percent = 0.03
|
||||
)
|
||||
// We use χ2 method to determine similarity of distribution with uniform distribution.
|
||||
// χ2 = Σ((n-N)**2/N)
|
||||
// https://www.medcalc.org/manual/chi-square-table.php p=0.1
|
||||
var chiTable = map[int]float64{9: 14.68, 99: 117.407}
|
||||
|
||||
t.Run("sortByWeight", func(t *testing.T) {
|
||||
var (
|
||||
i uint64
|
||||
size = uint64(10)
|
||||
nodes = make([]uint64, 0, size)
|
||||
counts = make(map[uint64]uint64)
|
||||
nodes [size]uint64
|
||||
counts = make(map[uint64]uint64, size)
|
||||
key = make([]byte, 16)
|
||||
keys = uint64(10000000)
|
||||
)
|
||||
|
||||
for i = 0; i < size; i++ {
|
||||
nodes = append(nodes, i)
|
||||
nodes[i] = i
|
||||
}
|
||||
|
||||
for i = 0; i < keys; i++ {
|
||||
binary.BigEndian.PutUint64(key, i)
|
||||
hash := hash(key)
|
||||
counts[SortByWeight(nodes, hash)[0]]++
|
||||
hash := Hash(key)
|
||||
counts[SortByWeight(nodes[:], hash)[0]]++
|
||||
}
|
||||
|
||||
mean := float64(keys) / float64(len(nodes))
|
||||
delta := mean * 0.01 // 1 %
|
||||
var chi2 float64
|
||||
mean := float64(keys) / float64(size)
|
||||
delta := mean * percent
|
||||
for node, count := range counts {
|
||||
d := mean - float64(count)
|
||||
chi2 += math.Pow(float64(count)-mean, 2) / mean
|
||||
if d > delta || (0-d) > delta {
|
||||
t.Errorf(
|
||||
"Node %d received %d keys, expected %v (+/- %v)",
|
||||
"Node %d received %d keys, expected %.0f (+/- %.2f)",
|
||||
node, count, mean, delta,
|
||||
)
|
||||
}
|
||||
}
|
||||
if chi2 > chiTable[size-1] {
|
||||
t.Errorf(
|
||||
"Chi2 condition for .9 is not met (expected %.2f <= %.2f)",
|
||||
chi2, chiTable[size-1])
|
||||
}
|
||||
})
|
||||
|
||||
t.Run("sortByIndex", func(t *testing.T) {
|
||||
var (
|
||||
i uint64
|
||||
a, b [size]uint64
|
||||
counts = make(map[uint64]int, size)
|
||||
key = make([]byte, 16)
|
||||
)
|
||||
|
||||
for i = 0; i < size; i++ {
|
||||
a[i] = i
|
||||
}
|
||||
|
||||
for i = 0; i < keys; i++ {
|
||||
copy(b[:], a[:])
|
||||
|
||||
binary.BigEndian.PutUint64(key, i)
|
||||
hash := Hash(key)
|
||||
SortSliceByIndex(b[:], hash)
|
||||
counts[b[0]]++
|
||||
}
|
||||
|
||||
var chi2 float64
|
||||
mean := float64(keys) / float64(size)
|
||||
delta := mean * percent
|
||||
for node, count := range counts {
|
||||
d := mean - float64(count)
|
||||
chi2 += math.Pow(float64(count)-mean, 2) / mean
|
||||
if d > delta || (0-d) > delta {
|
||||
t.Errorf(
|
||||
"Node %d received %d keys, expected %.0f (+/- %.2f)",
|
||||
node, count, mean, delta,
|
||||
)
|
||||
}
|
||||
}
|
||||
if chi2 > chiTable[size-1] {
|
||||
t.Errorf(
|
||||
"Chi2 condition for .9 is not met (expected %.2f <= %.2f)",
|
||||
chi2, chiTable[size-1])
|
||||
}
|
||||
})
|
||||
|
||||
t.Run("sortByValue", func(t *testing.T) {
|
||||
var (
|
||||
i uint64
|
||||
a, b [size]int
|
||||
counts = make(map[int]int, size)
|
||||
key = make([]byte, 16)
|
||||
)
|
||||
|
||||
for i = 0; i < size; i++ {
|
||||
a[i] = int(i)
|
||||
}
|
||||
|
||||
for i = 0; i < keys; i++ {
|
||||
copy(b[:], a[:])
|
||||
binary.BigEndian.PutUint64(key, i)
|
||||
hash := Hash(key)
|
||||
SortSliceByValue(b[:], hash)
|
||||
counts[b[0]]++
|
||||
}
|
||||
|
||||
var chi2 float64
|
||||
mean := float64(keys) / float64(size)
|
||||
delta := mean * percent
|
||||
for node, count := range counts {
|
||||
d := mean - float64(count)
|
||||
chi2 += math.Pow(float64(count)-mean, 2) / mean
|
||||
if d > delta || (0-d) > delta {
|
||||
t.Errorf(
|
||||
"Node %d received %d keys, expected %.0f (+/- %.2f)",
|
||||
node, count, mean, delta,
|
||||
)
|
||||
}
|
||||
}
|
||||
if chi2 > chiTable[size-1] {
|
||||
t.Errorf(
|
||||
"Chi2 condition for .9 is not met (expected %.2f <= %.2f)",
|
||||
chi2, chiTable[size-1])
|
||||
}
|
||||
})
|
||||
|
||||
t.Run("sortByStringValue", func(t *testing.T) {
|
||||
var (
|
||||
i uint64
|
||||
a, b [size]string
|
||||
counts = make(map[string]int, size)
|
||||
key = make([]byte, 16)
|
||||
)
|
||||
|
||||
for i = 0; i < size; i++ {
|
||||
a[i] = strconv.FormatUint(i, 10)
|
||||
}
|
||||
|
||||
for i = 0; i < keys; i++ {
|
||||
copy(b[:], a[:])
|
||||
binary.BigEndian.PutUint64(key, i)
|
||||
hash := Hash(key)
|
||||
SortSliceByValue(b[:], hash)
|
||||
counts[b[0]]++
|
||||
}
|
||||
|
||||
var chi2 float64
|
||||
mean := float64(keys) / float64(size)
|
||||
delta := mean * percent
|
||||
for node, count := range counts {
|
||||
d := mean - float64(count)
|
||||
chi2 += math.Pow(float64(count)-mean, 2) / mean
|
||||
if d > delta || (0-d) > delta {
|
||||
t.Errorf(
|
||||
"Node %s received %d keys, expected %.0f (+/- %.2f)",
|
||||
node, count, mean, delta,
|
||||
)
|
||||
}
|
||||
}
|
||||
if chi2 > chiTable[size-1] {
|
||||
t.Errorf(
|
||||
"Chi2 condition for .9 is not met (expected %.2f <= %.2f)",
|
||||
chi2, chiTable[size-1])
|
||||
}
|
||||
|
||||
})
|
||||
|
||||
t.Run("hash collision", func(t *testing.T) {
|
||||
var (
|
||||
i uint64
|
||||
counts = make(map[uint64]uint64)
|
||||
key = make([]byte, 16)
|
||||
)
|
||||
|
||||
for i = 0; i < keys; i++ {
|
||||
binary.BigEndian.PutUint64(key, i)
|
||||
hash := Hash(key)
|
||||
counts[hash]++
|
||||
}
|
||||
|
||||
for node, count := range counts {
|
||||
if count > 1 {
|
||||
t.Errorf("Node %d received %d keys", node, count)
|
||||
}
|
||||
}
|
||||
})
|
||||
}
|
||||
|
||||
func BenchmarkSortByWeight_fnv_10(b *testing.B) {
|
||||
hash := hash(testKey)
|
||||
hash := Hash(testKey)
|
||||
_ = benchmarkSortByWeight(b, 10, hash)
|
||||
}
|
||||
|
||||
func BenchmarkSortByWeight_fnv_100(b *testing.B) {
|
||||
hash := hash(testKey)
|
||||
hash := Hash(testKey)
|
||||
_ = benchmarkSortByWeight(b, 100, hash)
|
||||
}
|
||||
|
||||
func BenchmarkSortByWeight_fnv_1000(b *testing.B) {
|
||||
hash := hash(testKey)
|
||||
hash := Hash(testKey)
|
||||
_ = benchmarkSortByWeight(b, 1000, hash)
|
||||
}
|
||||
|
||||
func BenchmarkSortByIndex_fnv_10(b *testing.B) {
|
||||
hash := hash(testKey)
|
||||
hash := Hash(testKey)
|
||||
benchmarkSortByIndex(b, 10, hash)
|
||||
}
|
||||
|
||||
func BenchmarkSortByIndex_fnv_100(b *testing.B) {
|
||||
hash := hash(testKey)
|
||||
hash := Hash(testKey)
|
||||
benchmarkSortByIndex(b, 100, hash)
|
||||
}
|
||||
|
||||
func BenchmarkSortByIndex_fnv_1000(b *testing.B) {
|
||||
hash := hash(testKey)
|
||||
hash := Hash(testKey)
|
||||
benchmarkSortByIndex(b, 1000, hash)
|
||||
}
|
||||
|
||||
func BenchmarkSortByValue_fnv_10(b *testing.B) {
|
||||
hash := hash(testKey)
|
||||
hash := Hash(testKey)
|
||||
benchmarkSortByValue(b, 10, hash)
|
||||
}
|
||||
|
||||
func BenchmarkSortByValue_fnv_100(b *testing.B) {
|
||||
hash := hash(testKey)
|
||||
hash := Hash(testKey)
|
||||
benchmarkSortByValue(b, 100, hash)
|
||||
}
|
||||
|
||||
func BenchmarkSortByValue_fnv_1000(b *testing.B) {
|
||||
hash := hash(testKey)
|
||||
hash := Hash(testKey)
|
||||
benchmarkSortByValue(b, 1000, hash)
|
||||
}
|
||||
|
||||
|
|
@ -300,8 +435,6 @@ func benchmarkSortByValue(b *testing.B, n int, hash uint64) {
|
|||
b.ReportAllocs()
|
||||
|
||||
for i := 0; i < b.N; i++ {
|
||||
if err := SortSliceByValue(servers, hash); err != nil {
|
||||
b.Fatal(err)
|
||||
}
|
||||
SortSliceByValue(servers, hash)
|
||||
}
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in a new issue