github.com/nats-io/nats-server/v2@v2.11.0-preview.2/internal/fastrand/fastrand_test.go (about)

     1  // Copyright 2020-23 The LevelDB-Go, Pebble and NATS Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style license that can be found in
     3  // the LICENSE file.
     4  
     5  package fastrand
     6  
     7  import (
     8  	"math/rand"
     9  	"sync"
    10  	"testing"
    11  	"time"
    12  )
    13  
    14  type defaultRand struct {
    15  	mu  sync.Mutex
    16  	src rand.Source64
    17  }
    18  
    19  func newDefaultRand() *defaultRand {
    20  	r := &defaultRand{
    21  		src: rand.New(rand.NewSource(time.Now().UnixNano())),
    22  	}
    23  	return r
    24  }
    25  
    26  func (r *defaultRand) Uint32() uint32 {
    27  	r.mu.Lock()
    28  	i := uint32(r.src.Uint64())
    29  	r.mu.Unlock()
    30  	return i
    31  }
    32  
    33  func (r *defaultRand) Uint64() uint64 {
    34  	r.mu.Lock()
    35  	i := uint64(r.src.Uint64())
    36  	r.mu.Unlock()
    37  	return i
    38  }
    39  
    40  func BenchmarkFastRand32(b *testing.B) {
    41  	b.RunParallel(func(pb *testing.PB) {
    42  		for pb.Next() {
    43  			Uint32()
    44  		}
    45  	})
    46  }
    47  
    48  func BenchmarkFastRand64(b *testing.B) {
    49  	b.RunParallel(func(pb *testing.PB) {
    50  		for pb.Next() {
    51  			Uint64()
    52  		}
    53  	})
    54  }
    55  
    56  func BenchmarkDefaultRand32(b *testing.B) {
    57  	r := newDefaultRand()
    58  	b.RunParallel(func(pb *testing.PB) {
    59  		for pb.Next() {
    60  			r.Uint32()
    61  		}
    62  	})
    63  }
    64  
    65  func BenchmarkDefaultRand64(b *testing.B) {
    66  	r := newDefaultRand()
    67  	b.RunParallel(func(pb *testing.PB) {
    68  		for pb.Next() {
    69  			r.Uint64()
    70  		}
    71  	})
    72  }