BoltDB RAM omnomnom

bench.go

package main

import (
	"log"
	"runtime"
	"strconv"

	bolt "github.com/coreos/bbolt"
)

func main() {
	db, _ := bolt.Open("test.db", 0600, nil)
	defer db.Close()

	db.Update(func(tx *bolt.Tx) error {
		b, _ := tx.CreateBucketIfNotExists([]byte("test"))
		for i := 10000000; i < 20000000; i++ {
			key := strconv.Itoa(i)
			b.Put([]byte(key), []byte(""))

			if i%200000 == 0 {
				alloc, sys := getMemUsage()
				log.Printf("Key = '%v', Alloc = %4vM, Sys = %4vM", key, alloc, sys)
			}
		}
		return nil
	})
}

func getMemUsage() (uint64, uint64) {
	var m runtime.MemStats
	runtime.ReadMemStats(&m)
	return bToMb(m.Alloc), bToMb(m.Sys)
}

func bToMb(b uint64) uint64 {
	return b / 1024 / 1024
}

out.txt

% go run bench.go
2018/05/14 10:06:28 Key = '10000000', Alloc =    0M, Sys =    1M
2018/05/14 10:06:28 Key = '10200000', Alloc =   27M, Sys =   52M
2018/05/14 10:06:28 Key = '10400000', Alloc =   53M, Sys =   69M
2018/05/14 10:06:29 Key = '10600000', Alloc =   82M, Sys =  140M
2018/05/14 10:06:29 Key = '10800000', Alloc =  165M, Sys =  252M
2018/05/14 10:06:29 Key = '11000000', Alloc =  157M, Sys =  252M
2018/05/14 10:06:29 Key = '11200000', Alloc =  161M, Sys =  253M
2018/05/14 10:06:29 Key = '11400000', Alloc =  266M, Sys =  350M
2018/05/14 10:06:30 Key = '11600000', Alloc =  240M, Sys =  472M
2018/05/14 10:06:30 Key = '11800000', Alloc =  248M, Sys =  472M
2018/05/14 10:06:30 Key = '12000000', Alloc =  406M, Sys =  623M
2018/05/14 10:06:30 Key = '12200000', Alloc =  417M, Sys =  624M
2018/05/14 10:06:30 Key = '12400000', Alloc =  427M, Sys =  624M
2018/05/14 10:06:31 Key = '12600000', Alloc =  377M, Sys =  814M
2018/05/14 10:06:31 Key = '12800000', Alloc =  388M, Sys =  814M
2018/05/14 10:06:31 Key = '13000000', Alloc =  398M, Sys =  814M
2018/05/14 10:06:32 Key = '13200000', Alloc =  469M, Sys = 1052M
2018/05/14 10:06:32 Key = '13400000', Alloc =  479M, Sys = 1052M
2018/05/14 10:06:32 Key = '13600000', Alloc =  490M, Sys = 1052M
2018/05/14 10:06:32 Key = '13800000', Alloc =  788M, Sys = 1052M
2018/05/14 10:06:33 Key = '14000000', Alloc =  798M, Sys = 1053M
2018/05/14 10:06:33 Key = '14200000', Alloc =  809M, Sys = 1053M
2018/05/14 10:06:33 Key = '14400000', Alloc =  820M, Sys = 1053M
2018/05/14 10:06:33 Key = '14600000', Alloc =  830M, Sys = 1054M
2018/05/14 10:06:34 Key = '14800000', Alloc =  722M, Sys = 1054M
2018/05/14 10:06:34 Key = '15000000', Alloc =  733M, Sys = 1054M
2018/05/14 10:06:34 Key = '15200000', Alloc =  743M, Sys = 1054M
2018/05/14 10:06:34 Key = '15400000', Alloc =  754M, Sys = 1054M
2018/05/14 10:06:34 Key = '15600000', Alloc =  765M, Sys = 1054M
2018/05/14 10:06:35 Key = '15800000', Alloc =  775M, Sys = 1054M
2018/05/14 10:06:35 Key = '16000000', Alloc = 1234M, Sys = 1517M
2018/05/14 10:06:35 Key = '16200000', Alloc = 1245M, Sys = 1518M
2018/05/14 10:06:35 Key = '16400000', Alloc = 1256M, Sys = 1518M
2018/05/14 10:06:35 Key = '16600000', Alloc = 1266M, Sys = 1518M
2018/05/14 10:06:36 Key = '16800000', Alloc = 1277M, Sys = 1519M
2018/05/14 10:06:36 Key = '17000000', Alloc = 1288M, Sys = 1519M
2018/05/14 10:06:36 Key = '17200000', Alloc = 1298M, Sys = 1519M
2018/05/14 10:06:37 Key = '17400000', Alloc = 1123M, Sys = 2098M
2018/05/14 10:06:37 Key = '17600000', Alloc = 1134M, Sys = 2098M
2018/05/14 10:06:37 Key = '17800000', Alloc = 1145M, Sys = 2098M
2018/05/14 10:06:38 Key = '18000000', Alloc = 1155M, Sys = 2098M
2018/05/14 10:06:38 Key = '18200000', Alloc = 1166M, Sys = 2098M
2018/05/14 10:06:38 Key = '18400000', Alloc = 1177M, Sys = 2098M
2018/05/14 10:06:38 Key = '18600000', Alloc = 1187M, Sys = 2098M
2018/05/14 10:06:38 Key = '18800000', Alloc = 1198M, Sys = 2099M
2018/05/14 10:06:38 Key = '19000000', Alloc = 1209M, Sys = 2099M
2018/05/14 10:06:39 Key = '19200000', Alloc = 1920M, Sys = 2099M
2018/05/14 10:06:40 Key = '19400000', Alloc = 1412M, Sys = 2099M
2018/05/14 10:06:40 Key = '19600000', Alloc = 1423M, Sys = 2099M
2018/05/14 10:06:40 Key = '19800000', Alloc = 1433M, Sys = 2099M