Remove unused code

pkg/phlaredb/query/iters.go

@@ -6,11 +6,12 @@ import (
 	"fmt"
 	"io"
 	"math"
+	"strings"
 	"sync"
-	"sync/atomic"
 
 	"github.com/grafana/dskit/multierror"
 	"github.com/opentracing/opentracing-go"
+	"github.com/opentracing/opentracing-go/log"
 	"github.com/segmentio/parquet-go"
 
 	"github.com/grafana/phlare/pkg/iter"
@@ -279,22 +280,6 @@ func (t *RowNumber) Next(repetitionLevel, definitionLevel int) {
 	}
 }
 
-// nextSlow is the original implementation of next. it is kept to test against
-// the unrolled version above
-func (t *RowNumber) nextSlow(repetitionLevel, definitionLevel int) {
-	t[repetitionLevel]++
-
-	// New children up through the definition level
-	for i := repetitionLevel + 1; i <= definitionLevel; i++ {
-		t[i] = 0
-	}
-
-	// // Children past the definition level are undefined
-	for i := definitionLevel + 1; i < len(t); i++ {
-		t[i] = -1
-	}
-}
-
 // Skip rows at the root-level.
 func (t *RowNumber) Skip(numRows int64) {
 	t[0] += numRows
@@ -391,34 +376,7 @@ func NewErrIterator(err error) Iterator {
 	return iter.NewErrSeekIterator[*IteratorResult, RowNumberWithDefinitionLevel](err)
 }
 
-var columnIteratorPool = sync.Pool{
-	New: func() interface{} {
-		return &columnIteratorBuffer{}
-	},
-}
-
-func columnIteratorPoolGet(capacity, len int) *columnIteratorBuffer {
-	res := columnIteratorPool.Get().(*columnIteratorBuffer)
-	if cap(res.rowNumbers) < capacity {
-		res.rowNumbers = make([]RowNumber, capacity)
-	}
-	if cap(res.values) < capacity {
-		res.values = make([]parquet.Value, capacity)
-	}
-	res.rowNumbers = res.rowNumbers[:len]
-	res.values = res.values[:len]
-	return res
-}
-
-func columnIteratorPoolPut(b *columnIteratorBuffer) {
-	b.values = b.values[:cap(b.values)]
-	for i := range b.values {
-		b.values[i] = parquet.Value{}
-	}
-	columnIteratorPool.Put(b)
-}
-
-var columnIteratorResultPool = sync.Pool{
+var iteratorResultPool = sync.Pool{
 	New: func() interface{} {
 		return &IteratorResult{Entries: make([]struct {
 			k        string
@@ -428,48 +386,18 @@ var columnIteratorResultPool = sync.Pool{
 	},
 }
 
-func columnIteratorResultPoolGet() *IteratorResult {
-	res := columnIteratorResultPool.Get().(*IteratorResult)
+func iteratorResultPoolGet() *IteratorResult {
+	res := iteratorResultPool.Get().(*IteratorResult)
 	return res
 }
 
-func columnIteratorResultPoolPut(r *IteratorResult) {
+func iteratorResultPoolPut(r *IteratorResult) {
 	if r != nil {
 		r.Reset()
-		columnIteratorResultPool.Put(r)
+		iteratorResultPool.Put(r)
 	}
 }
 
-// ColumnIterator asynchronously iterates through the given row groups and column. Applies
-// the optional predicate to each chunk, page, and value.  Results are read by calling
-// Next() until it returns nil.
-type ColumnIterator struct {
-	rgs     []parquet.RowGroup
-	col     int
-	colName string
-	filter  *InstrumentedPredicate
-
-	selectAs string
-	seekTo   atomic.Value
-
-	metrics *Metrics
-	table   string
-	quit    chan struct{}
-	ch      chan *columnIteratorBuffer
-
-	curr  *columnIteratorBuffer
-	currN int
-
-	result *IteratorResult
-	err    error
-}
-
-type columnIteratorBuffer struct {
-	rowNumbers []RowNumber
-	values     []parquet.Value
-	err        error
-}
-
 type BinaryJoinIterator struct {
 	left            Iterator
 	right           Iterator
@@ -506,7 +434,7 @@ func (bj *BinaryJoinIterator) Next() bool {
 
 		if cmp := CompareRowNumbers(bj.definitionLevel, resLeft.RowNumber, resRight.RowNumber); cmp == 0 {
 			// we have a found an element
-			bj.res = columnIteratorResultPoolGet()
+			bj.res = iteratorResultPoolGet()
 			bj.res.RowNumber = resLeft.RowNumber
 			bj.res.Append(resLeft)
 			bj.res.Append(resRight)
@@ -644,7 +572,7 @@ func (j *JoinIterator) seekAll(to RowNumberWithDefinitionLevel) {
 	to.RowNumber = TruncateRowNumber(to)
 	for iterNum, iter := range j.iters {
 		if j.peeks[iterNum] == nil || CompareRowNumbers(to.DefinitionLevel, j.peeks[iterNum].RowNumber, to.RowNumber) == -1 {
-			columnIteratorResultPoolPut(j.peeks[iterNum])
+			iteratorResultPoolPut(j.peeks[iterNum])
 			if iter.Seek(to) {
 				j.peeks[iterNum] = iter.At()
 			} else {
@@ -667,15 +595,15 @@ func (j *JoinIterator) peek(iterNum int) *IteratorResult {
 // the next row (according to the configured definition level)
 // or are exhausted.
 func (j *JoinIterator) collect(rowNumber RowNumber) *IteratorResult {
-	result := columnIteratorResultPoolGet()
+	result := iteratorResultPoolGet()
 	result.RowNumber = rowNumber
 
 	for i := range j.iters {
 		for j.peeks[i] != nil && CompareRowNumbers(j.definitionLevel, j.peeks[i].RowNumber, rowNumber) == 0 {
 
 			result.Append(j.peeks[i])
 
-			columnIteratorResultPoolPut(j.peeks[i])
+			iteratorResultPoolPut(j.peeks[i])
 
 			if j.iters[i].Next() {
 				j.peeks[i] = j.iters[i].At()
@@ -809,15 +737,15 @@ func (u *UnionIterator) peek(iterNum int) *IteratorResult {
 // the next row (according to the configured definition level)
 // or are exhausted.
 func (u *UnionIterator) collect(iterNums []int, rowNumber RowNumber) *IteratorResult {
-	result := columnIteratorResultPoolGet()
+	result := iteratorResultPoolGet()
 	result.RowNumber = rowNumber
 
 	for _, iterNum := range iterNums {
 		for u.peeks[iterNum] != nil && CompareRowNumbers(u.definitionLevel, u.peeks[iterNum].RowNumber, rowNumber) == 0 {
 
 			result.Append(u.peeks[iterNum])
 
-			columnIteratorResultPoolPut(u.peeks[iterNum])
+			iteratorResultPoolPut(u.peeks[iterNum])
 
 			if u.iters[iterNum].Next() {
 				u.peeks[iterNum] = u.iters[iterNum].At()
@@ -928,7 +856,7 @@ func (r *RowNumberIterator[T]) Next() bool {
 	if !r.Iterator.Next() {
 		return false
 	}
-	r.current = columnIteratorResultPoolGet()
+	r.current = iteratorResultPoolGet()
 	r.current.Reset()
 	rowGetter, ok := any(r.Iterator.At()).(RowGetter)
 	if !ok {
@@ -975,6 +903,7 @@ type SyncIterator struct {
 	// Config
 	column     int
 	columnName string
+	table      string
 	rgs        []parquet.RowGroup
 	rgsMin     []RowNumber
 	rgsMax     []RowNumber // Exclusive, row number of next one past the row group
@@ -984,6 +913,7 @@ type SyncIterator struct {
 
 	// Status
 	span            opentracing.Span
+	metrics         *Metrics
 	curr            RowNumber
 	currRowGroup    parquet.RowGroup
 	currRowGroupMin RowNumber
@@ -1045,6 +975,8 @@ func NewSyncIterator(ctx context.Context, rgs []parquet.RowGroup, column int, co
 	})
 
 	return &SyncIterator{
+		table:      strings.ToLower(rgs[0].Schema().Name()) + "s",
+		metrics:    getMetricsFromContext(ctx),
 		span:       span,
 		column:     column,
 		columnName: columnName,
@@ -1209,6 +1141,12 @@ func (c *SyncIterator) seekPages(seekTo RowNumber, definitionLevel int) (done bo
 				c.closeCurrRowGroup()
 				return true, err
 			}
+			c.metrics.pageReadsTotal.WithLabelValues(c.table, c.columnName).Add(1)
+			c.span.LogFields(
+				log.String("msg", "reading page"),
+				log.Int64("page_num_values", pg.NumValues()),
+				log.Int64("page_size", pg.Size()),
+			)
 
 			// Skip based on row number?
 			newRN := c.curr
@@ -1365,7 +1303,7 @@ func (c *SyncIterator) closeCurrRowGroup() {
 }
 
 func (c *SyncIterator) makeResult(t RowNumber, v *parquet.Value) *IteratorResult {
-	r := columnIteratorResultPoolGet()
+	r := iteratorResultPoolGet()
 	r.RowNumber = t
 	if c.selectAs != "" {
 		r.AppendValue(c.selectAs, v.Clone())