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@starius
Created November 25, 2018 21:15
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package main
import (
"flag"
"fmt"
"io"
"math/rand"
"os"
"time"
"gitlab.com/NebulousLabs/Sia/modules"
)
var (
nsectors = flag.Int("nsectors", 100, "Total number of sectors (only 10-20% are used)")
)
func write(f io.WriterAt, i int) {
buffer := make([]byte, modules.SectorSize)
r := rand.New(rand.NewSource(int64(i)))
if n, err := r.Read(buffer); err != nil || n != len(buffer) {
panic("!!!")
}
if n, err := f.WriteAt(buffer, int64(i)*int64(modules.SectorSize)); err != nil || n != len(buffer) {
panic("!!!")
}
}
func punch(f modules.File, i int) {
if err := f.PunchHole(int64(i)*int64(modules.SectorSize), int64(modules.SectorSize)); err != nil {
panic(err)
}
}
func read(f io.ReaderAt, i int) {
buffer := make([]byte, modules.SectorSize)
if n, err := f.ReadAt(buffer, int64(i)*int64(modules.SectorSize)); err != nil || n != len(buffer) {
panic("!!!")
}
}
func main() {
flag.Parse()
r := rand.New(rand.NewSource(42))
allSectors := r.Perm(*nsectors)
toWrite := allSectors[:(*nsectors / 10)]
holes := allSectors[(*nsectors / 10):(2 * *nsectors / 10)]
var toWrite2 []int
toWrite2 = append(toWrite2, toWrite...)
toWrite2 = append(toWrite2, holes...)
toWrite2 = append(toWrite2, holes...)
r.Shuffle(len(toWrite2), func(i, j int) {
toWrite2[i], toWrite2[j] = toWrite2[j], toWrite2[i]
})
old, err := modules.ProdDependencies.OpenFile("old", os.O_CREATE|os.O_EXCL|os.O_RDWR, 0700)
if err != nil {
panic(err)
}
withPunchHoles, err := modules.ProdDependencies.OpenFile("withPunchHoles", os.O_CREATE|os.O_EXCL|os.O_RDWR, 0700)
if err != nil {
panic(err)
}
t1 := time.Now()
for _, i := range toWrite {
write(old, i)
}
fmt.Println("old write:", time.Since(t1)/time.Duration(len(toWrite)))
t1 = time.Now()
for _, i := range toWrite {
read(old, i)
}
fmt.Println("old read:", time.Since(t1)/time.Duration(len(toWrite)))
var totalWrite, totalPunch time.Duration
var writeCount, punchCount int
seen := make(map[int]struct{})
for _, i := range toWrite2 {
t1 = time.Now()
if _, has := seen[i]; !has {
seen[i] = struct{}{}
write(withPunchHoles, i)
totalWrite += time.Since(t1)
writeCount++
} else {
punch(withPunchHoles, i)
totalPunch += time.Since(t1)
punchCount++
}
}
fmt.Println("withPunchHoles write:", totalWrite/time.Duration(writeCount))
fmt.Println("withPunchHoles punch:", totalPunch/time.Duration(punchCount))
t1 = time.Now()
for _, i := range toWrite {
read(withPunchHoles, i)
}
fmt.Println("withPunchHoles read:", time.Since(t1)/time.Duration(len(toWrite)))
}
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