// Copyright 2014 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package btree
import (
"flag"
"fmt"
"math/rand"
"reflect"
"sort"
"sync"
"testing"
"time"
)
func init() {
seed := time.Now().Unix()
fmt.Println(seed)
rand.Seed(seed)
}
// perm returns a random permutation of n Int items in the range [0, n).
func perm(n int) (out []Item) {
for _, v := range rand.Perm(n) {
out = append(out, Int(v))
}
return
}
// rang returns an ordered list of Int items in the range [0, n).
func rang(n int) (out []Item) {
for i := 0; i < n; i++ {
out = append(out, Int(i))
}
return
}
// all extracts all items from a tree in order as a slice.
func all(t *BTree) (out []Item) {
t.Ascend(func(a Item) bool {
out = append(out, a)
return true
})
return
}
// rangerev returns a reversed ordered list of Int items in the range [0, n).
func rangrev(n int) (out []Item) {
for i := n - 1; i >= 0; i-- {
out = append(out, Int(i))
}
return
}
// allrev extracts all items from a tree in reverse order as a slice.
func allrev(t *BTree) (out []Item) {
t.Descend(func(a Item) bool {
out = append(out, a)
return true
})
return
}
var btreeDegree = flag.Int("degree", 32, "B-Tree degree")
func TestBTree(t *testing.T) {
tr := New(*btreeDegree)
const treeSize = 10000
for i := 0; i < 10; i++ {
if min := tr.Min(); min != nil {
t.Fatalf("empty min, got %+v", min)
}
if max := tr.Max(); max != nil {
t.Fatalf("empty max, got %+v", max)
}
for _, item := range perm(treeSize) {
if x := tr.ReplaceOrInsert(item); x != nil {
t.Fatal("insert found item", item)
}
}
for _, item := range perm(treeSize) {
if x := tr.ReplaceOrInsert(item); x == nil {
t.Fatal("insert didn't find item", item)
}
}
if min, want := tr.Min(), Item(Int(0)); min != want {
t.Fatalf("min: want %+v, got %+v", want, min)
}
if max, want := tr.Max(), Item(Int(treeSize-1)); max != want {
t.Fatalf("max: want %+v, got %+v", want, max)
}
got := all(tr)
want := rang(treeSize)
if !reflect.DeepEqual(got, want) {
t.Fatalf("mismatch:\n got: %v\nwant: %v", got, want)
}
gotrev := allrev(tr)
wantrev := rangrev(treeSize)
if !reflect.DeepEqual(gotrev, wantrev) {
t.Fatalf("mismatch:\n got: %v\nwant: %v", got, want)
}
for _, item := range perm(treeSize) {
if x := tr.Delete(item); x == nil {
t.Fatalf("didn't find %v", item)
}
}
if got = all(tr); len(got) > 0 {
t.Fatalf("some left!: %v", got)
}
}
}
func ExampleBTree() {
tr := New(*btreeDegree)
for i := Int(0); i < 10; i++ {
tr.ReplaceOrInsert(i)
}
fmt.Println("len: ", tr.Len())
fmt.Println("get3: ", tr.Get(Int(3)))
fmt.Println("get100: ", tr.Get(Int(100)))
fmt.Println("del4: ", tr.Delete(Int(4)))
fmt.Println("del100: ", tr.Delete(Int(100)))
fmt.Println("replace5: ", tr.ReplaceOrInsert(Int(5)))
fmt.Println("replace100:", tr.ReplaceOrInsert(Int(100)))
fmt.Println("min: ", tr.Min())
fmt.Println("delmin: ", tr.DeleteMin())
fmt.Println("max: ", tr.Max())
fmt.Println("delmax: ", tr.DeleteMax())
fmt.Println("len: ", tr.Len())
// Output:
// len: 10
// get3: 3
// get100: <nil>
// del4: 4
// del100: <nil>
// replace5: 5
// replace100: <nil>
// min: 0
// delmin: 0
// max: 100
// delmax: 100
// len: 8
}
func TestDeleteMin(t *testing.T) {
tr := New(3)
for _, v := range perm(100) {
tr.ReplaceOrInsert(v)
}
var got []Item
for v := tr.DeleteMin(); v != nil; v = tr.DeleteMin() {
got = append(got, v)
}
if want := rang(100); !reflect.DeepEqual(got, want) {
t.Fatalf("ascendrange:\n got: %v\nwant: %v", got, want)
}
}
func TestDeleteMax(t *testing.T) {
tr := New(3)
for _, v := range perm(100) {
tr.ReplaceOrInsert(v)
}
var got []Item
for v := tr.DeleteMax(); v != nil; v = tr.DeleteMax() {
got = append(got, v)
}
// Reverse our list.
for i := 0; i < len(got)/2; i++ {
got[i], got[len(got)-i-1] = got[len(got)-i-1], got[i]
}
if want := rang(100); !reflect.DeepEqual(got, want) {
t.Fatalf("ascendrange:\n got: %v\nwant: %v", got, want)
}
}
func TestAscendRange(t *testing.T) {
tr := New(2)
for _, v := range perm(100) {
tr.ReplaceOrInsert(v)
}
var got []Item
tr.AscendRange(Int(40), Int(60), func(a Item) bool {
got = append(got, a)
return true
})
if want := rang(100)[40:60]; !reflect.DeepEqual(got, want) {
t.Fatalf("ascendrange:\n got: %v\nwant: %v", got, want)
}
got = got[:0]
tr.AscendRange(Int(40), Int(60), func(a Item) bool {
if a.(Int) > 50 {
return false
}
got = append(got, a)
return true
})
if want := rang(100)[40:51]; !reflect.DeepEqual(got, want) {
t.Fatalf("ascendrange:\n got: %v\nwant: %v", got, want)
}
}
func TestDescendRange(t *testing.T) {
tr := New(2)
for _, v := range perm(100) {
tr.ReplaceOrInsert(v)
}
var got []Item
tr.DescendRange(Int(60), Int(40), func(a Item) bool {
got = append(got, a)
return true
})
if want := rangrev(100)[39:59]; !reflect.DeepEqual(got, want) {
t.Fatalf("descendrange:\n got: %v\nwant: %v", got, want)
}
got = got[:0]
tr.DescendRange(Int(60), Int(40), func(a Item) bool {
if a.(Int) < 50 {
return false
}
got = append(got, a)
return true
})
if want := rangrev(100)[39:50]; !reflect.DeepEqual(got, want) {
t.Fatalf("descendrange:\n got: %v\nwant: %v", got, want)
}
}
func TestAscendLessThan(t *testing.T) {
tr := New(*btreeDegree)
for _, v := range perm(100) {
tr.ReplaceOrInsert(v)
}
var got []Item
tr.AscendLessThan(Int(60), func(a Item) bool {
got = append(got, a)
return true
})
if want := rang(100)[:60]; !reflect.DeepEqual(got, want) {
t.Fatalf("ascendrange:\n got: %v\nwant: %v", got, want)
}
got = got[:0]
tr.AscendLessThan(Int(60), func(a Item) bool {
if a.(Int) > 50 {
return false
}
got = append(got, a)
return true
})
if want := rang(100)[:51]; !reflect.DeepEqual(got, want) {
t.Fatalf("ascendrange:\n got: %v\nwant: %v", got, want)
}
}
func TestDescendLessOrEqual(t *testing.T) {
tr := New(*btreeDegree)
for _, v := range perm(100) {
tr.ReplaceOrInsert(v)
}
var got []Item
tr.DescendLessOrEqual(Int(40), func(a Item) bool {
got = append(got, a)
return true
})
if want := rangrev(100)[59:]; !reflect.DeepEqual(got, want) {
t.Fatalf("descendlessorequal:\n got: %v\nwant: %v", got, want)
}
got = got[:0]
tr.DescendLessOrEqual(Int(60), func(a Item) bool {
if a.(Int) < 50 {
return false
}
got = append(got, a)
return true
})
if want := rangrev(100)[39:50]; !reflect.DeepEqual(got, want) {
t.Fatalf("descendlessorequal:\n got: %v\nwant: %v", got, want)
}
}
func TestAscendGreaterOrEqual(t *testing.T) {
tr := New(*btreeDegree)
for _, v := range perm(100) {
tr.ReplaceOrInsert(v)
}
var got []Item
tr.AscendGreaterOrEqual(Int(40), func(a Item) bool {
got = append(got, a)
return true
})
if want := rang(100)[40:]; !reflect.DeepEqual(got, want) {
t.Fatalf("ascendrange:\n got: %v\nwant: %v", got, want)
}
got = got[:0]
tr.AscendGreaterOrEqual(Int(40), func(a Item) bool {
if a.(Int) > 50 {
return false
}
got = append(got, a)
return true
})
if want := rang(100)[40:51]; !reflect.DeepEqual(got, want) {
t.Fatalf("ascendrange:\n got: %v\nwant: %v", got, want)
}
}
func TestDescendGreaterThan(t *testing.T) {
tr := New(*btreeDegree)
for _, v := range perm(100) {
tr.ReplaceOrInsert(v)
}
var got []Item
tr.DescendGreaterThan(Int(40), func(a Item) bool {
got = append(got, a)
return true
})
if want := rangrev(100)[:59]; !reflect.DeepEqual(got, want) {
t.Fatalf("descendgreaterthan:\n got: %v\nwant: %v", got, want)
}
got = got[:0]
tr.DescendGreaterThan(Int(40), func(a Item) bool {
if a.(Int) < 50 {
return false
}
got = append(got, a)
return true
})
if want := rangrev(100)[:50]; !reflect.DeepEqual(got, want) {
t.Fatalf("descendgreaterthan:\n got: %v\nwant: %v", got, want)
}
}
const benchmarkTreeSize = 10000
func BenchmarkInsert(b *testing.B) {
b.StopTimer()
insertP := perm(benchmarkTreeSize)
b.StartTimer()
i := 0
for i < b.N {
tr := New(*btreeDegree)
for _, item := range insertP {
tr.ReplaceOrInsert(item)
i++
if i >= b.N {
return
}
}
}
}
func BenchmarkSeek(b *testing.B) {
b.StopTimer()
size := 100000
insertP := perm(size)
tr := New(*btreeDegree)
for _, item := range insertP {
tr.ReplaceOrInsert(item)
}
b.StartTimer()
for i := 0; i < b.N; i++ {
tr.AscendGreaterOrEqual(Int(i%size), func(i Item) bool { return false })
}
}
func BenchmarkDeleteInsert(b *testing.B) {
b.StopTimer()
insertP := perm(benchmarkTreeSize)
tr := New(*btreeDegree)
for _, item := range insertP {
tr.ReplaceOrInsert(item)
}
b.StartTimer()
for i := 0; i < b.N; i++ {
tr.Delete(insertP[i%benchmarkTreeSize])
tr.ReplaceOrInsert(insertP[i%benchmarkTreeSize])
}
}
func BenchmarkDeleteInsertCloneOnce(b *testing.B) {
b.StopTimer()
insertP := perm(benchmarkTreeSize)
tr := New(*btreeDegree)
for _, item := range insertP {
tr.ReplaceOrInsert(item)
}
tr = tr.Clone()
b.StartTimer()
for i := 0; i < b.N; i++ {
tr.Delete(insertP[i%benchmarkTreeSize])
tr.ReplaceOrInsert(insertP[i%benchmarkTreeSize])
}
}
func BenchmarkDeleteInsertCloneEachTime(b *testing.B) {
b.StopTimer()
insertP := perm(benchmarkTreeSize)
tr := New(*btreeDegree)
for _, item := range insertP {
tr.ReplaceOrInsert(item)
}
b.StartTimer()
for i := 0; i < b.N; i++ {
tr = tr.Clone()
tr.Delete(insertP[i%benchmarkTreeSize])
tr.ReplaceOrInsert(insertP[i%benchmarkTreeSize])
}
}
func BenchmarkDelete(b *testing.B) {
b.StopTimer()
insertP := perm(benchmarkTreeSize)
removeP := perm(benchmarkTreeSize)
b.StartTimer()
i := 0
for i < b.N {
b.StopTimer()
tr := New(*btreeDegree)
for _, v := range insertP {
tr.ReplaceOrInsert(v)
}
b.StartTimer()
for _, item := range removeP {
tr.Delete(item)
i++
if i >= b.N {
return
}
}
if tr.Len() > 0 {
panic(tr.Len())
}
}
}
func BenchmarkGet(b *testing.B) {
b.StopTimer()
insertP := perm(benchmarkTreeSize)
removeP := perm(benchmarkTreeSize)
b.StartTimer()
i := 0
for i < b.N {
b.StopTimer()
tr := New(*btreeDegree)
for _, v := range insertP {
tr.ReplaceOrInsert(v)
}
b.StartTimer()
for _, item := range removeP {
tr.Get(item)
i++
if i >= b.N {
return
}
}
}
}
func BenchmarkGetCloneEachTime(b *testing.B) {
b.StopTimer()
insertP := perm(benchmarkTreeSize)
removeP := perm(benchmarkTreeSize)
b.StartTimer()
i := 0
for i < b.N {
b.StopTimer()
tr := New(*btreeDegree)
for _, v := range insertP {
tr.ReplaceOrInsert(v)
}
b.StartTimer()
for _, item := range removeP {
tr = tr.Clone()
tr.Get(item)
i++
if i >= b.N {
return
}
}
}
}
type byInts []Item
func (a byInts) Len() int {
return len(a)
}
func (a byInts) Less(i, j int) bool {
return a[i].(Int) < a[j].(Int)
}
func (a byInts) Swap(i, j int) {
a[i], a[j] = a[j], a[i]
}
func BenchmarkAscend(b *testing.B) {
arr := perm(benchmarkTreeSize)
tr := New(*btreeDegree)
for _, v := range arr {
tr.ReplaceOrInsert(v)
}
sort.Sort(byInts(arr))
b.ResetTimer()
for i := 0; i < b.N; i++ {
j := 0
tr.Ascend(func(item Item) bool {
if item.(Int) != arr[j].(Int) {
b.Fatalf("mismatch: expected: %v, got %v", arr[j].(Int), item.(Int))
}
j++
return true
})
}
}
func BenchmarkDescend(b *testing.B) {
arr := perm(benchmarkTreeSize)
tr := New(*btreeDegree)
for _, v := range arr {
tr.ReplaceOrInsert(v)
}
sort.Sort(byInts(arr))
b.ResetTimer()
for i := 0; i < b.N; i++ {
j := len(arr) - 1
tr.Descend(func(item Item) bool {
if item.(Int) != arr[j].(Int) {
b.Fatalf("mismatch: expected: %v, got %v", arr[j].(Int), item.(Int))
}
j--
return true
})
}
}
func BenchmarkAscendRange(b *testing.B) {
arr := perm(benchmarkTreeSize)
tr := New(*btreeDegree)
for _, v := range arr {
tr.ReplaceOrInsert(v)
}
sort.Sort(byInts(arr))
b.ResetTimer()
for i := 0; i < b.N; i++ {
j := 100
tr.AscendRange(Int(100), arr[len(arr)-100], func(item Item) bool {
if item.(Int) != arr[j].(Int) {
b.Fatalf("mismatch: expected: %v, got %v", arr[j].(Int), item.(Int))
}
j++
return true
})
if j != len(arr)-100 {
b.Fatalf("expected: %v, got %v", len(arr)-100, j)
}
}
}
func BenchmarkDescendRange(b *testing.B) {
arr := perm(benchmarkTreeSize)
tr := New(*btreeDegree)
for _, v := range arr {
tr.ReplaceOrInsert(v)
}
sort.Sort(byInts(arr))
b.ResetTimer()
for i := 0; i < b.N; i++ {
j := len(arr) - 100
tr.DescendRange(arr[len(arr)-100], Int(100), func(item Item) bool {
if item.(Int) != arr[j].(Int) {
b.Fatalf("mismatch: expected: %v, got %v", arr[j].(Int), item.(Int))
}
j--
return true
})
if j != 100 {
b.Fatalf("expected: %v, got %v", len(arr)-100, j)
}
}
}
func BenchmarkAscendGreaterOrEqual(b *testing.B) {
arr := perm(benchmarkTreeSize)
tr := New(*btreeDegree)
for _, v := range arr {
tr.ReplaceOrInsert(v)
}
sort.Sort(byInts(arr))
b.ResetTimer()
for i := 0; i < b.N; i++ {
j := 100
k := 0
tr.AscendGreaterOrEqual(Int(100), func(item Item) bool {
if item.(Int) != arr[j].(Int) {
b.Fatalf("mismatch: expected: %v, got %v", arr[j].(Int), item.(Int))
}
j++
k++
return true
})
if j != len(arr) {
b.Fatalf("expected: %v, got %v", len(arr), j)
}
if k != len(arr)-100 {
b.Fatalf("expected: %v, got %v", len(arr)-100, k)
}
}
}
func BenchmarkDescendLessOrEqual(b *testing.B) {
arr := perm(benchmarkTreeSize)
tr := New(*btreeDegree)
for _, v := range arr {
tr.ReplaceOrInsert(v)
}
sort.Sort(byInts(arr))
b.ResetTimer()
for i := 0; i < b.N; i++ {
j := len(arr) - 100
k := len(arr)
tr.DescendLessOrEqual(arr[len(arr)-100], func(item Item) bool {
if item.(Int) != arr[j].(Int) {
b.Fatalf("mismatch: expected: %v, got %v", arr[j].(Int), item.(Int))
}
j--
k--
return true
})
if j != -1 {
b.Fatalf("expected: %v, got %v", -1, j)
}
if k != 99 {
b.Fatalf("expected: %v, got %v", 99, k)
}
}
}
const cloneTestSize = 10000
func cloneTest(t *testing.T, b *BTree, start int, p []Item, wg *sync.WaitGroup, trees *[]*BTree) {
t.Logf("Starting new clone at %v", start)
*trees = append(*trees, b)
for i := start; i < cloneTestSize; i++ {
b.ReplaceOrInsert(p[i])
if i%(cloneTestSize/5) == 0 {
wg.Add(1)
go cloneTest(t, b.Clone(), i+1, p, wg, trees)
}
}
wg.Done()
}
func TestCloneConcurrentOperations(t *testing.T) {
b := New(*btreeDegree)
trees := []*BTree{}
p := perm(cloneTestSize)
var wg sync.WaitGroup
wg.Add(1)
go cloneTest(t, b, 0, p, &wg, &trees)
wg.Wait()
want := rang(cloneTestSize)
t.Logf("Starting equality checks on %d trees", len(trees))
for i, tree := range trees {
if !reflect.DeepEqual(want, all(tree)) {
t.Errorf("tree %v mismatch", i)
}
}
t.Log("Removing half from first half")
toRemove := rang(cloneTestSize)[cloneTestSize/2:]
for i := 0; i < len(trees)/2; i++ {
tree := trees[i]
wg.Add(1)
go func() {
for _, item := range toRemove {
tree.Delete(item)
}
wg.Done()
}()
}
wg.Wait()
t.Log("Checking all values again")
for i, tree := range trees {
var wantpart []Item
if i < len(trees)/2 {
wantpart = want[:cloneTestSize/2]
} else {
wantpart = want
}
if got := all(tree); !reflect.DeepEqual(wantpart, got) {
t.Errorf("tree %v mismatch, want %v got %v", i, len(want), len(got))
}
}
}
func BenchmarkDeleteAndRestore(b *testing.B) {
items := perm(16392)
b.ResetTimer()
b.Run(`CopyBigFreeList`, func(b *testing.B) {
fl := NewFreeList(16392)
tr := NewWithFreeList(*btreeDegree, fl)
for _, v := range items {
tr.ReplaceOrInsert(v)
}
b.ReportAllocs()
b.ResetTimer()
for i := 0; i < b.N; i++ {
dels := make([]Item, 0, tr.Len())
tr.Ascend(ItemIterator(func(b Item) bool {
dels = append(dels, b)
return true
}))
for _, del := range dels {
tr.Delete(del)
}
// tr is now empty, we make a new empty copy of it.
tr = NewWithFreeList(*btreeDegree, fl)
for _, v := range items {
tr.ReplaceOrInsert(v)
}
}
})
b.Run(`Copy`, func(b *testing.B) {
tr := New(*btreeDegree)
for _, v := range items {
tr.ReplaceOrInsert(v)
}
b.ReportAllocs()
b.ResetTimer()
for i := 0; i < b.N; i++ {
dels := make([]Item, 0, tr.Len())
tr.Ascend(ItemIterator(func(b Item) bool {
dels = append(dels, b)
return true
}))
for _, del := range dels {
tr.Delete(del)
}
// tr is now empty, we make a new empty copy of it.
tr = New(*btreeDegree)
for _, v := range items {
tr.ReplaceOrInsert(v)
}
}
})
b.Run(`ClearBigFreelist`, func(b *testing.B) {
fl := NewFreeList(16392)
tr := NewWithFreeList(*btreeDegree, fl)
for _, v := range items {
tr.ReplaceOrInsert(v)
}
b.ReportAllocs()
b.ResetTimer()
for i := 0; i < b.N; i++ {
tr.Clear(true)
for _, v := range items {
tr.ReplaceOrInsert(v)
}
}
})
b.Run(`Clear`, func(b *testing.B) {
tr := New(*btreeDegree)
for _, v := range items {
tr.ReplaceOrInsert(v)
}
b.ReportAllocs()
b.ResetTimer()
for i := 0; i < b.N; i++ {
tr.Clear(true)
for _, v := range items {
tr.ReplaceOrInsert(v)
}
}
})
}