Merge pull request #11 from semihbkgr/memtable-bytes-evaluation

Fixing the calculation of memtable bytes

Author: krasun

lsmtree.go

@@ -33,11 +33,11 @@ const (
 var (
 	// ErrKeyRequired is returned when putting a zero-length key or nil.
 	ErrKeyRequired = errors.New("key required")
-	// ErrKeyRequired is returned when putting a zero-length value or nil.
+	// ErrValueRequired is returned when putting a zero-length value or nil.
 	ErrValueRequired = errors.New("value required")
 	// ErrKeyTooLarge is returned when putting a key that is larger than MaxKeySize.
 	ErrKeyTooLarge = errors.New("key too large")
-	// ErrKeyTooLarge is returned when putting a value that is larger than MaxValueSize.
+	// ErrValueTooLarge is returned when putting a value that is larger than MaxValueSize.
 	ErrValueTooLarge = errors.New("value too large")
 )
 

memtable.go

@@ -41,6 +41,8 @@ func (mt *memTable) get(key []byte) ([]byte, bool) {
 func (mt *memTable) delete(key []byte) error {
 	value, exists := mt.data.Put(key, nil)
 	if !exists {
+		mt.b += len(key)
+	} else {
 		mt.b -= len(value)
 	}
 

memtable_test.go

@@ -0,0 +1,103 @@
+package lsmtree
+
+import (
+	"math/rand"
+	"testing"
+	"time"
+)
+
+func TestMemTable_put(t *testing.T) {
+	const keySize = 64
+	const valueSize = 1024
+	const length = 100
+	mt := newMemTable()
+	for i := 0; i < length; i++ {
+		err := mt.put(randBytes(keySize), randBytes(valueSize))
+		if err != nil {
+			t.Error(err)
+		}
+	}
+	if mt.data.Size() != length {
+		t.Errorf("length of underlying tree is not as expected, expected: %d, actual: %d", length, mt.data.Size())
+	}
+	expectedSize := (keySize + valueSize) * length
+	if mt.bytes() != expectedSize {
+		t.Errorf("size of data is not as expected, expected: %d, actual: %d", expectedSize, mt.bytes())
+	}
+}
+
+func TestMemTable_get(t *testing.T) {
+	const length = 100
+	mt := newMemTable()
+	keys := make([][]byte, 0, length)
+	for i := 0; i < length; i++ {
+		key := randBytes(64)
+		keys = append(keys, key)
+		err := mt.put(key, randBytes(1024))
+		if err != nil {
+			t.Error(err)
+		}
+	}
+	for _, k := range keys {
+		_, ok := mt.get(k)
+		if !ok {
+			t.Error("the key does not exist in memtable")
+		}
+	}
+}
+
+func TestMemTable_delete(t *testing.T) {
+	const keySize = 64
+	const length = 100
+	mt := newMemTable()
+	keys := make([][]byte, 0, length)
+	for i := 0; i < length; i++ {
+		key := randBytes(keySize)
+		keys = append(keys, key)
+		err := mt.put(key, randBytes(1024))
+		if err != nil {
+			t.Error(err)
+		}
+	}
+	for _, k := range keys {
+		err := mt.delete(k)
+		if err != nil {
+			t.Error(err)
+		}
+	}
+	if mt.data.Size() != length {
+		t.Errorf("length of underlying tree is not as expected, expected: %d, actual: %d", length, mt.data.Size())
+	}
+	expectedSize := keySize * length
+	if mt.bytes() != expectedSize {
+		t.Errorf("size of data is not as expected, expected: %d, actual: %d", expectedSize, mt.bytes())
+	}
+}
+
+func TestMemTable_clear(t *testing.T) {
+	const length = 100
+	mt := newMemTable()
+	for i := 0; i < length; i++ {
+		err := mt.put(randBytes(64), randBytes(1024))
+		if err != nil {
+			t.Error(err)
+		}
+	}
+	mt.clear()
+	if mt.data.Size() != 0 {
+		t.Errorf("length of underlying tree is not zero, actual: %d", mt.data.Size())
+	}
+	if mt.bytes() != 0 {
+		t.Errorf("size of data is not zero, actual: %d", mt.bytes())
+	}
+}
+
+var r = rand.New(rand.NewSource(time.Now().Unix()))
+
+func randBytes(size int) []byte {
+	b := make([]byte, 0, size)
+	for i := 0; i < size; i++ {
+		b = append(b, byte(r.Uint32()))
+	}
+	return b
+}