blob: e7e23505e5b71ef25dff6ef9d1fff6b8163f9b12 [file] [log] [blame]
package lru
import (
"math/rand"
"testing"
)
func BenchmarkLRU_Rand(b *testing.B) {
l, err := New(8192)
if err != nil {
b.Fatalf("err: %v", err)
}
trace := make([]int64, b.N*2)
for i := 0; i < b.N*2; i++ {
trace[i] = rand.Int63() % 32768
}
b.ResetTimer()
var hit, miss int
for i := 0; i < 2*b.N; i++ {
if i%2 == 0 {
l.Add(trace[i], trace[i])
} else {
_, ok := l.Get(trace[i])
if ok {
hit++
} else {
miss++
}
}
}
b.Logf("hit: %d miss: %d ratio: %f", hit, miss, float64(hit)/float64(miss))
}
func BenchmarkLRU_Freq(b *testing.B) {
l, err := New(8192)
if err != nil {
b.Fatalf("err: %v", err)
}
trace := make([]int64, b.N*2)
for i := 0; i < b.N*2; i++ {
if i%2 == 0 {
trace[i] = rand.Int63() % 16384
} else {
trace[i] = rand.Int63() % 32768
}
}
b.ResetTimer()
for i := 0; i < b.N; i++ {
l.Add(trace[i], trace[i])
}
var hit, miss int
for i := 0; i < b.N; i++ {
_, ok := l.Get(trace[i])
if ok {
hit++
} else {
miss++
}
}
b.Logf("hit: %d miss: %d ratio: %f", hit, miss, float64(hit)/float64(miss))
}
func TestLRU(t *testing.T) {
evictCounter := 0
onEvicted := func(k interface{}, v interface{}) {
if k != v {
t.Fatalf("Evict values not equal (%v!=%v)", k, v)
}
evictCounter++
}
l, err := NewWithEvict(128, onEvicted)
if err != nil {
t.Fatalf("err: %v", err)
}
for i := 0; i < 256; i++ {
l.Add(i, i)
}
if l.Len() != 128 {
t.Fatalf("bad len: %v", l.Len())
}
if evictCounter != 128 {
t.Fatalf("bad evict count: %v", evictCounter)
}
for i, k := range l.Keys() {
if v, ok := l.Get(k); !ok || v != k || v != i+128 {
t.Fatalf("bad key: %v", k)
}
}
for i := 0; i < 128; i++ {
_, ok := l.Get(i)
if ok {
t.Fatalf("should be evicted")
}
}
for i := 128; i < 256; i++ {
_, ok := l.Get(i)
if !ok {
t.Fatalf("should not be evicted")
}
}
for i := 128; i < 192; i++ {
l.Remove(i)
_, ok := l.Get(i)
if ok {
t.Fatalf("should be deleted")
}
}
l.Get(192) // expect 192 to be last key in l.Keys()
for i, k := range l.Keys() {
if (i < 63 && k != i+193) || (i == 63 && k != 192) {
t.Fatalf("out of order key: %v", k)
}
}
l.Purge()
if l.Len() != 0 {
t.Fatalf("bad len: %v", l.Len())
}
if _, ok := l.Get(200); ok {
t.Fatalf("should contain nothing")
}
}
// test that Add returns true/false if an eviction occurred
func TestLRUAdd(t *testing.T) {
evictCounter := 0
onEvicted := func(k interface{}, v interface{}) {
evictCounter++
}
l, err := NewWithEvict(1, onEvicted)
if err != nil {
t.Fatalf("err: %v", err)
}
if l.Add(1, 1) == true || evictCounter != 0 {
t.Errorf("should not have an eviction")
}
if l.Add(2, 2) == false || evictCounter != 1 {
t.Errorf("should have an eviction")
}
}
// test that Contains doesn't update recent-ness
func TestLRUContains(t *testing.T) {
l, err := New(2)
if err != nil {
t.Fatalf("err: %v", err)
}
l.Add(1, 1)
l.Add(2, 2)
if !l.Contains(1) {
t.Errorf("1 should be contained")
}
l.Add(3, 3)
if l.Contains(1) {
t.Errorf("Contains should not have updated recent-ness of 1")
}
}
// test that Contains doesn't update recent-ness
func TestLRUContainsOrAdd(t *testing.T) {
l, err := New(2)
if err != nil {
t.Fatalf("err: %v", err)
}
l.Add(1, 1)
l.Add(2, 2)
contains, evict := l.ContainsOrAdd(1, 1)
if !contains {
t.Errorf("1 should be contained")
}
if evict {
t.Errorf("nothing should be evicted here")
}
l.Add(3, 3)
contains, evict = l.ContainsOrAdd(1, 1)
if contains {
t.Errorf("1 should not have been contained")
}
if !evict {
t.Errorf("an eviction should have occurred")
}
if !l.Contains(1) {
t.Errorf("now 1 should be contained")
}
}
// test that Peek doesn't update recent-ness
func TestLRUPeek(t *testing.T) {
l, err := New(2)
if err != nil {
t.Fatalf("err: %v", err)
}
l.Add(1, 1)
l.Add(2, 2)
if v, ok := l.Peek(1); !ok || v != 1 {
t.Errorf("1 should be set to 1: %v, %v", v, ok)
}
l.Add(3, 3)
if l.Contains(1) {
t.Errorf("should not have updated recent-ness of 1")
}
}