update readme

Author: dsa0x

cmd/main.go

@@ -6,14 +6,15 @@ import (
 	"runtime"
 	"time"
 
+	"github.com/dgraph-io/badger/v3"
 	"github.com/dsa0x/sprout"
 	bolt "go.etcd.io/bbolt"
 )
 
 func main() {
 	num := 20_000_00
 	// div := num / 10
-	// main6()
+	// main7()
 	// return
 	opts := &sprout.BloomOptions{
 		Err_rate: 0.001,
@@ -118,3 +119,36 @@ func main6() {
 		}
 	}
 }
+func main7() {
+	num := 2_000_000
+	db, err := badger.Open(badger.DefaultOptions("badgerstore.db"))
+	if err != nil {
+		panic(err)
+	}
+	err = db.Update(func(tx *badger.Txn) error {
+		for i := 0; i < num; i++ {
+			err := tx.Set([]byte(fmt.Sprintf("i%d-j", i)), []byte("b"))
+			if err != nil {
+				return err
+			}
+		}
+		return err
+	})
+	for i := 0; i < 100; i++ {
+		err = db.Update(func(tx *badger.Txn) error {
+			for j := 0; j < num/100; j++ {
+				err := tx.Set([]byte(fmt.Sprintf("i%d-j%d", i, j)), []byte("b"))
+				if err != nil {
+					return err
+				}
+			}
+			return nil
+		})
+		if err != nil {
+			break
+		}
+	}
+	if err != nil {
+		log.Fatal(err)
+	}
+}

readme.md

@@ -10,16 +10,22 @@ Sprout also implement a scalable bloom filter described in a paper written by [P
 
 A scalable bloom filter allows you to grow the filter beyond the initial filter capacity, while preserving the desired false positive rate.
 
-### Memory Usage
+### Storage Size
 
 Bloom filters are space efficient, as they only store the bits that are set. For a filter with a capacity of 2,000,000 and a error rate of 0.001, the storage size is approximately 3.4MB. That implies that there are approximately 1.8 bytes (~14 bits) per element.
 The number of bits per element is as a result of the number of hash functions, which is derived from the capacity and the error rate.
 
-In comparison, adding 2 million elements (with a singly byte value) to a boltdb database uses a storage size of about 108MB (113 bytes per pair).
+**Scalable Bloom Filters**: A scalable bloom filter initialized with a capacity of 2,000,000 and an error rate of 0.001, when grown to a capacity of 20,000,000, the total storage size is approximately 37.3MB.
 
-**Scalable Bloom Filters**
+**Comparison to Key-Value stores**
 
-A scalable bloom filter initialized with a capacity of 2,000,000 and an error rate of 0.001, when grown to a capacity of 20,000,000, the total storage size is approximately 37.3MB.
+Adding 2 million elements (with a single byte value)
+
+| Database | Size  |
+| -------- | ----- |
+| BoltDB   | 108MB |
+| BadgerDB | 128MB |
+| Sprout   | 3.4MB |
 
 ### Installation