improved?

Author: James Cor

sql/rowexec/join_iters.go

@@ -189,6 +189,8 @@ func (i *joinIter) Next(ctx *sql.Context) (sql.Row, error) {
 		}
 
 		if !sql.IsTrue(res) {
+			// TODO: we are trashing row here, so we can release the memory...right?
+			i.rowBuffer.Erase(i.rowSize)
 			continue
 		}
 
@@ -212,9 +214,8 @@ func (i *joinIter) buildRow(primary, secondary sql.Row) sql.Row {
 }
 
 func (i *joinIter) Close(ctx *sql.Context) (err error) {
-	//i.rowBuffer.Reset()
-	//sql.RowBufPool.Put(i.rowBuffer)
-	i.rowBuffer = nil
+	i.rowBuffer.Reset()
+	sql.RowBufPool.Put(i.rowBuffer)
 
 	if i.primary != nil {
 		if err = i.primary.Close(ctx); err != nil {
@@ -417,9 +418,8 @@ func (i *existsIter) buildRow(primary, secondary sql.Row) sql.Row {
 }
 
 func (i *existsIter) Close(ctx *sql.Context) (err error) {
-	i.rowBuffer = nil
-	//i.rowBuffer.Reset()
-	//sql.RowBufPool.Put(i.rowBuffer)
+	i.rowBuffer.Reset()
+	sql.RowBufPool.Put(i.rowBuffer)
 
 	if i.primary != nil {
 		if err = i.primary.Close(ctx); err != nil {
@@ -589,9 +589,8 @@ func (i *fullJoinIter) buildRow(primary, secondary sql.Row) sql.Row {
 }
 
 func (i *fullJoinIter) Close(ctx *sql.Context) (err error) {
-	i.rowBuffer = nil
-	//i.rowBuffer.Reset()
-	//sql.RowBufPool.Put(i.rowBuffer)
+	i.rowBuffer.Reset()
+	sql.RowBufPool.Put(i.rowBuffer)
 
 	if i.l != nil {
 		err = i.l.Close(ctx)
@@ -709,9 +708,8 @@ func (i *crossJoinIterator) removeParentRow(r sql.Row) sql.Row {
 }
 
 func (i *crossJoinIterator) Close(ctx *sql.Context) (err error) {
-	i.rowBuffer = nil
-	//i.rowBuffer.Reset()
-	//sql.RowBufPool.Put(i.rowBuffer)
+	i.rowBuffer.Reset()
+	sql.RowBufPool.Put(i.rowBuffer)
 
 	if i.l != nil {
 		err = i.l.Close(ctx)
@@ -913,9 +911,8 @@ func (i *lateralJoinIterator) Next(ctx *sql.Context) (sql.Row, error) {
 }
 
 func (i *lateralJoinIterator) Close(ctx *sql.Context) error {
-	i.rowBuffer = nil
-	//i.rowBuffer.Reset()
-	//sql.RowBufPool.Put(i.rowBuffer)
+	i.rowBuffer.Reset()
+	sql.RowBufPool.Put(i.rowBuffer)
 
 	var lerr, rerr error
 	if i.lIter != nil {

sql/rows.go

@@ -84,7 +84,7 @@ func FormatRow(row Row) string {
 	return sb.String()
 }
 
-const defaultRowBuffCap = 4096
+const defaultRowBufCap = 128
 
 type RowBuffer struct {
 	i   int
@@ -93,27 +93,37 @@ type RowBuffer struct {
 
 func NewRowBuffer() *RowBuffer {
 	return &RowBuffer{
-		buf: make(Row, defaultRowBuffCap),
+		buf: make(Row, 0, defaultRowBufCap),
 	}
 }
 
 func (b *RowBuffer) Get(n int) (res Row) {
 	newI := b.i + n
-	if newI >= len(b.buf) {
-		//b.buf = append(b.buf, b.buf) // TODO: not sure if this is correct, but it seems faster
-		buf := make(Row, len(b.buf)*2)
-		copy(b.buf, buf)
+	if newI >= cap(b.buf) {
+		buf := make(Row, newI*2) // Golang is stupid, don't let it decide the new capacity
+		copy(buf, b.buf)
 		b.buf = buf
 	}
+	b.buf = b.buf[:newI]
+	for i := b.i; i < newI; i++ {
+		b.buf[i] = nil
+	}
 	res = b.buf[b.i:newI]
 	b.i = newI
 	return
 }
 
 func (b *RowBuffer) Reset() {
+	for i := 0; i < b.i; i++ {
+		b.buf[i] = nil
+	}
 	b.i = 0
 }
 
+func (b *RowBuffer) Erase(i int) {
+	b.i -= i
+}
+
 var RowBufPool = sync.Pool{
 	New: func() any {
 		return NewRowBuffer()