gistfile1.go

package main

import (
	"encoding/binary"
	"fmt"
	"github.com/coocood/freecache"
	"github.com/davecheney/profile"
	"log"
	"math/rand"
	"runtime"
	"sync"
	"sync/atomic"
	"time"
)

func main() {
	runtime.GOMAXPROCS(runtime.NumCPU())

	defer profile.Start(profile.CPUProfile).Stop()
	_ = profile.Start
	_ = log.Print
	_ = rand.Uint32
	_ = time.NewTicker

	const cache_size = 1 * 1024 * 1024
	cache := freecache.NewCache(cache_size)

	value_buf := []byte("129nadanh2[0h3r2k3 42,m 3232 3m2 43m2 1931231DSSASADASDADSAaaaaaaaaaaaaajb23ijeb23u4e2h3")

	const key_len = 16
	const n_routines = 1 //10
	value_total_len := uint64(0)
	n_keys := 1 * 1000 * 1000

	// rmain := rand.New(rand.NewSource(time.Now().UnixNano()))
	// r := rand.NewZipf(rmain, 2.0, 71.0, uint64(len(value_buf)))

	var wg sync.WaitGroup

	for k := 0; k < n_routines; k++ {
		wg.Add(1)
		go func(k int) {
			for i := 0; i < n_keys; i++ {
				var key [16]byte

				// k1 := rand.Intn(1000000000)
				// k2 := k1 + rand.Intn(1000000000)
				// binary.LittleEndian.PutUint64(key[:8], uint64(k1)) //uint64(i*k+1000000))
				// binary.LittleEndian.PutUint64(key[8:], uint64(k2)) //20394390473*i*k+1000000))

				// binary.LittleEndian.PutUint64(key[:8], uint64(i*k+1000000))
				// binary.LittleEndian.PutUint64(key[8:], uint64(20394390473*i*k+1000000))

				binary.LittleEndian.PutUint64(key[:8], uint64(i))
				binary.LittleEndian.PutUint64(key[8:], uint64(i))

				// upper_bound := uint(r.Uint64()) //rand.Intn(len(value_buf))
				upper_bound := rand.Intn(len(value_buf))
				// upper_bound := 16 //len(value_buf)
				atomic.AddUint64(&value_total_len, uint64(upper_bound))

				// log.Printf(">> %d setting key: %v\n", k, key[:])
				cache.Set(key[:], value_buf[:upper_bound], 0)
				// log.Printf("<< %d setting key: %v\n", k, key[:])
			}

			wg.Done()
		}(k)
	}

	wg.Wait()

	avg_value_len := float64(value_total_len) / float64(n_routines) / float64(n_keys)
	bytes_per_item := float64(cache_size) / float64(cache.EntryCount())

	fmt.Printf("entries: %d, evacuated: %d, overwritten: %d\n", cache.EntryCount(), cache.EvacuateCount(), cache.OverwriteCount())
	fmt.Printf("avg_value_len: %v\n", avg_value_len)
	fmt.Printf("bytes per item: %v - %v - %v = %v\n", bytes_per_item, avg_value_len, key_len, bytes_per_item-avg_value_len-key_len)
}