func TestCorrectness() {
fmt.Printf("Correctness test\n")
for ii := 0; ii < 20; ii++ {
rnd := rand.New(rand.NewSource(time.Now().UnixNano()))
fmt.Printf("\nTest %v\n", ii)
var arr []int
if ii == 0 {
arr = []int{0, 0, 1, 1, 2, 2, 3, 3}
} else if ii == 1 {
arr = make([]int, 500)
for i := range arr {
arr[i] = 8
}
arr[0] = 1
} else if ii == 2 {
arr = []int{0, 1, 2, 2, 2, 2, 7, 9, 9, 16, 16, 16, 1, 3,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3}
} else {
arr = make([]int, 1024)
idx := 0
for idx < len(arr) {
length := rnd.Intn(270)
if length%3 == 0 {
length = 1
}
val := rand.Intn(256) - 128
end := idx + length
if end >= len(arr) {
end = len(arr) - 1
}
for j := idx; j < end; j++ {
arr[j] = val
}
idx += length
fmt.Printf("%v (%v) ", val, length)
}
}
size := len(arr)
input := make([]byte, size)
output := make([]byte, 32+size*4/3)
reverse := make([]byte, size)
for i := range output {
output[i] = 0xAA
}
for i := range arr {
input[i] = byte(arr[i])
}
snappy, _ := function.NewSnappyCodec(0)
fmt.Printf("\nOriginal: ")
for i := range arr {
fmt.Printf("%v ", input[i])
}
srcIdx, dstIdx, err := snappy.Forward(input, output)
if err != nil {
fmt.Printf("\n===Encoding error===\n%v\n", err)
os.Exit(1)
}
if srcIdx != uint(len(input)) {
fmt.Printf("\nNo compression (ratio > 1.0), skip reverse")
continue
}
fmt.Printf("\nCoded: ")
for i := uint(0); i < dstIdx; i++ {
fmt.Printf("%v ", output[i])
}
// Required to reset internal attributes
snappy, _ = function.NewSnappyCodec(dstIdx)
_, _, err = snappy.Inverse(output, reverse)
if err != nil {
fmt.Printf("\n===Decoding error===\n%v\n", err)
os.Exit(1)
}
fmt.Printf("\nDecoded: ")
for i := range reverse {
fmt.Printf("%v ", reverse[i])
}
fmt.Printf("\n")
// Check
for i := range reverse {
if input[i] != reverse[i] {
fmt.Printf("Different (index %v - %v)\n", input[i], reverse[i])
os.Exit(1)
}
}
fmt.Printf("Identical\n")
}
}
func TestSpeed() {
iter := 50000
size := 30000
fmt.Printf("\n\nSpeed test\n")
fmt.Printf("Iterations: %v\n", iter)
for jj := 0; jj < 3; jj++ {
input := make([]byte, size)
output := make([]byte, 32+size*4/3)
reverse := make([]byte, size)
// Generate random data with runs
n := 0
delta1 := int64(0)
delta2 := int64(0)
for n < len(input) {
val := byte(rand.Intn(3))
input[n] = val
n++
run := rand.Intn(255)
run -= 200
run--
for run > 0 && n < len(input) {
input[n] = val
n++
run--
}
}
var dstIdx uint
var err error
for ii := 0; ii < iter; ii++ {
snappy, _ := function.NewSnappyCodec(0)
before := time.Now()
_, dstIdx, err = snappy.Forward(input, output)
if err != nil {
fmt.Printf("Encoding error%v\n", err)
os.Exit(1)
}
after := time.Now()
delta1 += after.Sub(before).Nanoseconds()
}
for ii := 0; ii < iter; ii++ {
snappy, _ := function.NewSnappyCodec(dstIdx)
before := time.Now()
if _, _, err = snappy.Inverse(output, reverse); err != nil {
fmt.Printf("Decoding error%v\n", err)
os.Exit(1)
}
after := time.Now()
delta2 += after.Sub(before).Nanoseconds()
}
idx := -1
// Sanity check
for i := range input {
if input[i] != reverse[i] {
idx = i
break
}
}
if idx >= 0 {
fmt.Printf("Failure at index %v (%v <-> %v)\n", idx, input[idx], reverse[idx])
os.Exit(1)
}
prod := int64(iter) * int64(size)
fmt.Printf("\nSnappy encoding [ms]: %v", delta1/1000000)
fmt.Printf("\nThroughput [MB/s] : %d", prod*1000000/delta1*1000/(1024*1024))
fmt.Printf("\nSnappy decoding [ms]: %v", delta2/1000000)
fmt.Printf("\nThroughput [MB/s] : %d", prod*1000000/delta2*1000/(1024*1024))
println()
}
}