wip

app/vlselect/logsql/logsql.go

@@ -1,6 +1,7 @@
 package logsql
 
 import (
+	"context"
 	"net/http"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlstorage"
@@ -17,8 +18,8 @@ var (
 		"too big value for this flag may result in high memory usage since the sorting is performed in memory")
 )
 
-// ProcessQueryRequest handles /select/logsql/query request
-func ProcessQueryRequest(w http.ResponseWriter, r *http.Request, stopCh <-chan struct{}, cancel func()) {
+// ProcessQueryRequest handles /select/logsql/query request.
+func ProcessQueryRequest(ctx context.Context, w http.ResponseWriter, r *http.Request) {
 	// Extract tenantID
 	tenantID, err := logstorage.GetTenantIDFromRequest(r)
 	if err != nil {
@@ -42,14 +43,18 @@ func ProcessQueryRequest(w http.ResponseWriter, r *http.Request, stopCh <-chan s
 	sw := getSortWriter()
 	sw.Init(w, maxSortBufferSize.IntN(), limit)
 	tenantIDs := []logstorage.TenantID{tenantID}
-	vlstorage.RunQuery(tenantIDs, q, stopCh, func(_ uint, rowsCount int, columns []logstorage.BlockColumn) {
+
+	ctxWithCancel, cancel := context.WithCancel(ctx)
+	defer cancel()
+
+	writeBlock := func(_ uint, timestamps []int64, columns []logstorage.BlockColumn) {
 		if len(columns) == 0 {
 			return
 		}
 
 		bb := blockResultPool.Get()
-		for rowIdx := 0; rowIdx < rowsCount; rowIdx++ {
-			WriteJSONRow(bb, columns, rowIdx)
+		for i := range timestamps {
+			WriteJSONRow(bb, columns, i)
 		}
 
 		if !sw.TryWrite(bb.B) {
@@ -57,7 +62,10 @@ func ProcessQueryRequest(w http.ResponseWriter, r *http.Request, stopCh <-chan s
 		}
 
 		blockResultPool.Put(bb)
-	})
+	}
+
+	vlstorage.RunQuery(ctxWithCancel, tenantIDs, q, writeBlock)
+
 	sw.FinalFlush()
 	putSortWriter(sw)
 }

app/vlselect/main.go

@@ -1,7 +1,6 @@
 package vlselect
 
 import (
-	"context"
 	"embed"
 	"flag"
 	"fmt"
@@ -141,15 +140,11 @@ func RequestHandler(w http.ResponseWriter, r *http.Request) bool {
 		}
 	}
 
-	ctxWithCancel, cancel := context.WithCancel(ctx)
-	defer cancel()
-	stopCh = ctxWithCancel.Done()
-
 	switch {
 	case path == "/logsql/query":
 		logsqlQueryRequests.Inc()
 		httpserver.EnableCORS(w, r)
-		logsql.ProcessQueryRequest(w, r, stopCh, cancel)
+		logsql.ProcessQueryRequest(ctx, w, r)
 		return true
 	default:
 		return false

app/vlstorage/main.go

@@ -1,6 +1,7 @@
 package vlstorage
 
 import (
+	"context"
 	"flag"
 	"fmt"
 	"net/http"
@@ -99,9 +100,9 @@ func MustAddRows(lr *logstorage.LogRows) {
 	strg.MustAddRows(lr)
 }
 
-// RunQuery runs the given q and calls processBlock for the returned data blocks
-func RunQuery(tenantIDs []logstorage.TenantID, q *logstorage.Query, stopCh <-chan struct{}, processBlock func(workerID uint, rowsCount int, columns []logstorage.BlockColumn)) {
-	strg.RunQuery(tenantIDs, q, stopCh, processBlock)
+// RunQuery runs the given q and calls writeBlock for the returned data blocks
+func RunQuery(ctx context.Context, tenantIDs []logstorage.TenantID, q *logstorage.Query, writeBlock func(workerID uint, timestamps []int64, columns []logstorage.BlockColumn)) {
+	strg.RunQuery(ctx, tenantIDs, q, writeBlock)
 }
 
 func initStorageMetrics(strg *logstorage.Storage) *metrics.Set {

lib/logstorage/pipes.go

@@ -2,13 +2,59 @@ package logstorage
 
 import (
 	"fmt"
+	"slices"
+	"strconv"
 	"strings"
+	"unsafe"
 
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/encoding"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 )
 
 type pipe interface {
+	// String returns string representation of the pipe.
 	String() string
+
+	// newPipeProcessor must return new pipeProcessor for the given ppBase.
+	//
+	// workersCount is the number of goroutine workers, which will call writeBlock() method.
+	//
+	// If stopCh is closed, the returned pipeProcessor must stop performing CPU-intensive tasks which take more than a few milliseconds.
+	// It is OK to continue processing pipeProcessor calls if they take less than a few milliseconds.
+	//
+	// The returned pipeProcessor may call cancel() at any time in order to stop ppBase.
+	newPipeProcessor(workersCount int, stopCh <-chan struct{}, cancel func(), ppBase pipeProcessor) pipeProcessor
+}
+
+// pipeProcessor must process a single pipe.
+type pipeProcessor interface {
+	// writeBlock must write the given block of data to the given pipeProcessor.
+	//
+	// The workerID is the id of the worker goroutine, which called the writeBlock.
+	// It is in the range 0 ... workersCount-1 .
+	//
+	// It is forbidden to hold references to columns after returning from writeBlock, since the caller re-uses columns.
+	writeBlock(workerID uint, timestamps []int64, columns []BlockColumn)
+
+	// flush must flush all the data accumulated in the pipeProcessor to the base pipeProcessor.
+	//
+	// The pipeProcessor must call ppBase.flush() and cancel(), which has been passed to newPipeProcessor, before returning from the flush.
+	flush()
+}
+
+type defaultPipeProcessor func(workerID uint, timestamps []int64, columns []BlockColumn)
+
+func newDefaultPipeProcessor(writeBlock func(workerID uint, timestamps []int64, columns []BlockColumn)) pipeProcessor {
+	return defaultPipeProcessor(writeBlock)
+}
+
+func (dpp defaultPipeProcessor) writeBlock(workerID uint, timestamps []int64, columns []BlockColumn) {
+	dpp(workerID, timestamps, columns)
+}
+
+func (dpp defaultPipeProcessor) flush() {
+	// Nothing to do
 }
 
 func parsePipes(lex *lexer) ([]pipe, error) {
@@ -52,6 +98,47 @@ func (fp *fieldsPipe) String() string {
 	return "fields " + fieldNamesString(fp.fields)
 }
 
+func (fp *fieldsPipe) newPipeProcessor(_ int, _ <-chan struct{}, cancel func(), ppBase pipeProcessor) pipeProcessor {
+	return &fieldsPipeProcessor{
+		fp:     fp,
+		cancel: cancel,
+		ppBase: ppBase,
+	}
+}
+
+type fieldsPipeProcessor struct {
+	fp     *fieldsPipe
+	cancel func()
+	ppBase pipeProcessor
+}
+
+func (fpp *fieldsPipeProcessor) writeBlock(workerID uint, timestamps []int64, columns []BlockColumn) {
+	if slices.Contains(fpp.fp.fields, "*") || areSameBlockColumns(columns, fpp.fp.fields) {
+		// Fast path - there is no need in additional transformations before writing the block to ppBase.
+		fpp.ppBase.writeBlock(workerID, timestamps, columns)
+		return
+	}
+
+	// Slow path - construct columns for fpp.fp.fields before writing them to ppBase.
+	brs := getBlockRows()
+	cs := brs.cs
+	for _, f := range fpp.fp.fields {
+		values := getValuesForBlockColumn(columns, f, len(timestamps))
+		cs = append(cs, BlockColumn{
+			Name:   f,
+			Values: values,
+		})
+	}
+	fpp.ppBase.writeBlock(workerID, timestamps, cs)
+	brs.cs = cs
+	putBlockRows(brs)
+}
+
+func (fpp *fieldsPipeProcessor) flush() {
+	fpp.ppBase.flush()
+	fpp.cancel()
+}
+
 func parseFieldsPipe(lex *lexer) (*fieldsPipe, error) {
 	var fields []string
 	for {
@@ -87,6 +174,27 @@ type statsFunc interface {
 
 	// neededFields returns the needed fields for calculating the given stats
 	neededFields() []string
+
+	// newStatsFuncProcessor must create new statsFuncProcessor for calculating stats for the given statsFunc.
+	newStatsFuncProcessor() statsFuncProcessor
+}
+
+// statsFuncProcessor must process stats for some statsFunc.
+//
+// All the statsFuncProcessor methods are called from a single goroutine at a time,
+// so there is no need in the internal synchronization.
+type statsFuncProcessor interface {
+	// updateStatsForAllRows must update statsFuncProcessor stats from all the rows.
+	updateStatsForAllRows(timestamps []int64, columns []BlockColumn)
+
+	// updateStatsForRow must update statsFuncProcessor stats from the row at rowIndex.
+	updateStatsForRow(timestamps []int64, columns []BlockColumn, rowIndex int)
+
+	// mergeState must merge sfp state into statsFuncProcessor state.
+	mergeState(sfp statsFuncProcessor)
+
+	// finalizeStats must return the collected stats from statsFuncProcessor.
+	finalizeStats() (name, value string)
 }
 
 func (sp *statsPipe) String() string {
@@ -106,6 +214,192 @@ func (sp *statsPipe) String() string {
 	return s
 }
 
+func (sp *statsPipe) newPipeProcessor(workersCount int, stopCh <-chan struct{}, cancel func(), ppBase pipeProcessor) pipeProcessor {
+	shards := make([]statsPipeProcessorShard, workersCount)
+	for i := range shards {
+		shard := &shards[i]
+		shard.m = make(map[string]*statsPipeGroup)
+		shard.funcs = sp.funcs
+	}
+
+	return &statsPipeProcessor{
+		sp:     sp,
+		stopCh: stopCh,
+		cancel: cancel,
+		ppBase: ppBase,
+
+		shards: shards,
+	}
+}
+
+type statsPipeProcessor struct {
+	sp     *statsPipe
+	stopCh <-chan struct{}
+	cancel func()
+	ppBase pipeProcessor
+
+	shards []statsPipeProcessorShard
+}
+
+type statsPipeProcessorShard struct {
+	statsPipeProcessorShardNopad
+
+	// The padding prevents false sharing on widespread platforms with
+	// 128 mod (cache line size) = 0 .
+	_ [128 - unsafe.Sizeof(statsPipeProcessorShardNopad{})%128]byte
+}
+
+type statsPipeProcessorShardNopad struct {
+	m     map[string]*statsPipeGroup
+	funcs []statsFunc
+
+	columnIdxs []int
+	keyBuf     []byte
+}
+
+func (shard *statsPipeProcessorShard) getStatsPipeGroup(key []byte) *statsPipeGroup {
+	spg := shard.m[string(key)]
+	if spg != nil {
+		return spg
+	}
+	sfps := make([]statsFuncProcessor, len(shard.funcs))
+	for i, f := range shard.funcs {
+		sfps[i] = f.newStatsFuncProcessor()
+	}
+	spg = &statsPipeGroup{
+		sfps: sfps,
+	}
+	shard.m[string(key)] = spg
+	return spg
+}
+
+type statsPipeGroup struct {
+	sfps []statsFuncProcessor
+}
+
+func (spp *statsPipeProcessor) writeBlock(workerID uint, timestamps []int64, columns []BlockColumn) {
+	shard := &spp.shards[workerID]
+
+	if len(spp.sp.byFields) == 0 {
+		// Fast path - pass all the rows to a single group
+		spg := shard.getStatsPipeGroup(nil)
+		for _, sfp := range spg.sfps {
+			sfp.updateStatsForAllRows(timestamps, columns)
+		}
+		return
+	}
+
+	// Slow path - update per-row stats
+
+	// Pre-calculate column indexes for byFields in order to speed up building group key in the loop below.
+	columnIdxs := shard.columnIdxs[:0]
+	for _, f := range spp.sp.byFields {
+		idx := getBlockColumnIndex(columns, f)
+		columnIdxs = append(columnIdxs, idx)
+	}
+	shard.columnIdxs = columnIdxs
+
+	keyBuf := shard.keyBuf
+	for i := range timestamps {
+		// Construct key for the by (...) fields
+		keyBuf = keyBuf[:0]
+		for _, idx := range columnIdxs {
+			v := ""
+			if idx >= 0 {
+				v = columns[idx].Values[i]
+			}
+			keyBuf = encoding.MarshalBytes(keyBuf, bytesutil.ToUnsafeBytes(v))
+		}
+
+		spg := shard.getStatsPipeGroup(keyBuf)
+		for _, sfp := range spg.sfps {
+			sfp.updateStatsForRow(timestamps, columns, i)
+		}
+	}
+	shard.keyBuf = keyBuf
+}
+
+func (spp *statsPipeProcessor) flush() {
+	defer func() {
+		spp.ppBase.flush()
+		spp.cancel()
+	}()
+
+	// Merge states across shards
+	shards := spp.shards
+	m := shards[0].m
+	shards = shards[1:]
+	for i := range shards {
+		shard := &shards[i]
+		for key, spg := range shard.m {
+			// shard.m may be quite big, so this loop can take a lot of time and CPU.
+			// Stop processing data as soon as stopCh is closed without wasting CPU time.
+			select {
+			case <-spp.stopCh:
+				return
+			default:
+			}
+
+			spgBase := m[key]
+			if spgBase == nil {
+				m[key] = spg
+			} else {
+				for i, sfp := range spgBase.sfps {
+					sfp.mergeState(spg.sfps[i])
+				}
+			}
+		}
+	}
+
+	// Write per-group states to ppBase
+	byFields := spp.sp.byFields
+	var values []string
+	var columns []BlockColumn
+	for key, spg := range m {
+		// m may be quite big, so this loop can take a lot of time and CPU.
+		// Stop processing data as soon as stopCh is closed without wasting CPU time.
+		select {
+		case <-spp.stopCh:
+			return
+		default:
+		}
+
+		// Unmarshal values for byFields from key.
+		values = values[:0]
+		keyBuf := bytesutil.ToUnsafeBytes(key)
+		for len(keyBuf) > 0 {
+			tail, v, err := encoding.UnmarshalBytes(keyBuf)
+			if err != nil {
+				logger.Panicf("BUG: cannot unmarshal value from keyBuf=%q: %w", keyBuf, err)
+			}
+			values = append(values, bytesutil.ToUnsafeString(v))
+			keyBuf = tail
+		}
+		if len(values) != len(byFields) {
+			logger.Panicf("BUG: unexpected number of values decoded from keyBuf; got %d; want %d", len(values), len(byFields))
+		}
+
+		// construct columns for byFields
+		columns = columns[:0]
+		for i, f := range byFields {
+			columns = append(columns, BlockColumn{
+				Name:   f,
+				Values: values[i : i+1],
+			})
+		}
+
+		// construct columns for stats functions
+		for _, sfp := range spg.sfps {
+			name, value := sfp.finalizeStats()
+			columns = append(columns, BlockColumn{
+				Name:   name,
+				Values: []string{value},
+			})
+		}
+		spp.ppBase.writeBlock(0, []int64{0}, columns)
+	}
+}
+
 func (sp *statsPipe) neededFields() []string {
 	var neededFields []string
 	m := make(map[string]struct{})
@@ -184,10 +478,39 @@ func (sfc *statsFuncCount) String() string {
 	return "count(" + fieldNamesString(fields) + ") as " + quoteTokenIfNeeded(sfc.resultName)
 }
 
+func (sfc *statsFuncCount) newStatsFuncProcessor() statsFuncProcessor {
+	return &statsFuncCountProcessor{
+		sfc: sfc,
+	}
+}
+
 func (sfc *statsFuncCount) neededFields() []string {
 	return getFieldsIgnoreStar(sfc.fields)
 }
 
+type statsFuncCountProcessor struct {
+	sfc       *statsFuncCount
+	rowsCount uint64
+}
+
+func (sfcp *statsFuncCountProcessor) updateStatsForAllRows(timestamps []int64, _ []BlockColumn) {
+	sfcp.rowsCount += uint64(len(timestamps))
+}
+
+func (sfcp *statsFuncCountProcessor) updateStatsForRow(_ []int64, _ []BlockColumn, _ int) {
+	sfcp.rowsCount++
+}
+
+func (sfcp *statsFuncCountProcessor) mergeState(sfp statsFuncProcessor) {
+	src := sfp.(*statsFuncCountProcessor)
+	sfcp.rowsCount += src.rowsCount
+}
+
+func (sfcp *statsFuncCountProcessor) finalizeStats() (string, string) {
+	value := strconv.FormatUint(sfcp.rowsCount, 10)
+	return sfcp.sfc.resultName, value
+}
+
 func parseStatsFuncCount(lex *lexer) (*statsFuncCount, error) {
 	lex.nextToken()
 	fields, err := parseFieldNamesInParens(lex)

lib/logstorage/storage_search.go

@@ -1,9 +1,11 @@
 package logstorage
 
 import (
+	"context"
 	"math"
 	"sort"
 	"sync"
+	"sync/atomic"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/cgroup"
 )
@@ -42,8 +44,8 @@ type searchOptions struct {
 	resultColumnNames []string
 }
 
-// RunQuery runs the given q and calls processBlock for results
-func (s *Storage) RunQuery(tenantIDs []TenantID, q *Query, stopCh <-chan struct{}, processBlock func(workerID uint, rowsCount int, columns []BlockColumn)) {
+// RunQuery runs the given q and calls writeBlock for results.
+func (s *Storage) RunQuery(ctx context.Context, tenantIDs []TenantID, q *Query, writeBlock func(workerID uint, timestamps []int64, columns []BlockColumn)) {
 	resultColumnNames := q.getResultColumnNames()
 	so := &genericSearchOptions{
 		tenantIDs:         tenantIDs,
@@ -52,6 +54,17 @@ func (s *Storage) RunQuery(tenantIDs []TenantID, q *Query, stopCh <-chan struct{
 	}
 
 	workersCount := cgroup.AvailableCPUs()
+
+	pp := newDefaultPipeProcessor(writeBlock)
+	stopCh := ctx.Done()
+	for i := len(q.pipes) - 1; i >= 0; i-- {
+		p := q.pipes[i]
+		ctxChild, cancel := context.WithCancel(ctx)
+		stopCh = ctxChild.Done()
+		pp = p.newPipeProcessor(workersCount, stopCh, cancel, pp)
+		ctx = ctxChild
+	}
+
 	s.search(workersCount, so, stopCh, func(workerID uint, br *blockResult) {
 		brs := getBlockRows()
 		cs := brs.cs
@@ -62,12 +75,13 @@ func (s *Storage) RunQuery(tenantIDs []TenantID, q *Query, stopCh <-chan struct{
 				Values: br.getColumnValues(i),
 			})
 		}
-		rowsCount := br.RowsCount()
-		processBlock(workerID, rowsCount, cs)
+		pp.writeBlock(workerID, br.timestamps, cs)
 
 		brs.cs = cs
 		putBlockRows(brs)
 	})
+
+	pp.flush()
 }
 
 type blockRows struct {
@@ -111,6 +125,53 @@ func (c *BlockColumn) reset() {
 	c.Values = nil
 }
 
+func areSameBlockColumns(columns []BlockColumn, columnNames []string) bool {
+	if len(columnNames) != len(columns) {
+		return false
+	}
+	for i, name := range columnNames {
+		if columns[i].Name != name {
+			return false
+		}
+	}
+	return true
+}
+
+func getBlockColumnIndex(columns []BlockColumn, columnName string) int {
+	for i, c := range columns {
+		if c.Name == columnName {
+			return i
+		}
+	}
+	return -1
+}
+
+func getValuesForBlockColumn(columns []BlockColumn, columnName string, rowsCount int) []string {
+	for _, c := range columns {
+		if c.Name == columnName {
+			return c.Values
+		}
+	}
+	return getEmptyStrings(rowsCount)
+}
+
+func getEmptyStrings(rowsCount int) []string {
+	p := emptyStrings.Load()
+	if p == nil {
+		values := make([]string, rowsCount)
+		emptyStrings.Store(&values)
+		return values
+	}
+	values := *p
+	if n := rowsCount - cap(values); n > 0 {
+		values = append(values[:cap(values)], make([]string, n)...)
+		emptyStrings.Store(&values)
+	}
+	return values[:rowsCount]
+}
+
+var emptyStrings atomic.Pointer[[]string]
+
 // The number of blocks to search at once by a single worker
 //
 // This number must be increased on systems with many CPU cores in order to amortize

lib/logstorage/storage_search_test.go

@@ -1,6 +1,7 @@
 package logstorage
 
 import (
+	"context"
 	"fmt"
 	"regexp"
 	"sync/atomic"
@@ -84,11 +85,11 @@ func TestStorageRunQuery(t *testing.T) {
 			AccountID: 0,
 			ProjectID: 0,
 		}
-		processBlock := func(_ uint, rowsCount int, _ []BlockColumn) {
-			panic(fmt.Errorf("unexpected match for %d rows", rowsCount))
+		writeBlock := func(_ uint, timestamps []int64, _ []BlockColumn) {
+			panic(fmt.Errorf("unexpected match for %d rows", len(timestamps)))
 		}
 		tenantIDs := []TenantID{tenantID}
-		s.RunQuery(tenantIDs, q, nil, processBlock)
+		s.RunQuery(context.Background(), tenantIDs, q, writeBlock)
 	})
 	t.Run("missing-message-text", func(_ *testing.T) {
 		q := mustParseQuery(`foobar`)
@@ -96,11 +97,11 @@ func TestStorageRunQuery(t *testing.T) {
 			AccountID: 1,
 			ProjectID: 11,
 		}
-		processBlock := func(_ uint, rowsCount int, _ []BlockColumn) {
-			panic(fmt.Errorf("unexpected match for %d rows", rowsCount))
+		writeBlock := func(_ uint, timestamps []int64, _ []BlockColumn) {
+			panic(fmt.Errorf("unexpected match for %d rows", len(timestamps)))
 		}
 		tenantIDs := []TenantID{tenantID}
-		s.RunQuery(tenantIDs, q, nil, processBlock)
+		s.RunQuery(context.Background(), tenantIDs, q, writeBlock)
 	})
 	t.Run("matching-tenant-id", func(t *testing.T) {
 		q := mustParseQuery(`tenant.id:*`)
@@ -111,14 +112,14 @@ func TestStorageRunQuery(t *testing.T) {
 			}
 			expectedTenantID := tenantID.String()
 			var rowsCountTotal atomic.Uint32
-			processBlock := func(_ uint, rowsCount int, columns []BlockColumn) {
+			writeBlock := func(_ uint, timestamps []int64, columns []BlockColumn) {
 				hasTenantIDColumn := false
 				var columnNames []string
 				for _, c := range columns {
 					if c.Name == "tenant.id" {
 						hasTenantIDColumn = true
-						if len(c.Values) != rowsCount {
-							panic(fmt.Errorf("unexpected number of rows in column %q; got %d; want %d", c.Name, len(c.Values), rowsCount))
+						if len(c.Values) != len(timestamps) {
+							panic(fmt.Errorf("unexpected number of rows in column %q; got %d; want %d", c.Name, len(c.Values), len(timestamps)))
 						}
 						for _, v := range c.Values {
 							if v != expectedTenantID {
@@ -131,10 +132,10 @@ func TestStorageRunQuery(t *testing.T) {
 				if !hasTenantIDColumn {
 					panic(fmt.Errorf("missing tenant.id column among columns: %q", columnNames))
 				}
-				rowsCountTotal.Add(uint32(len(columns[0].Values)))
+				rowsCountTotal.Add(uint32(len(timestamps)))
 			}
 			tenantIDs := []TenantID{tenantID}
-			s.RunQuery(tenantIDs, q, nil, processBlock)
+			s.RunQuery(context.Background(), tenantIDs, q, writeBlock)
 
 			expectedRowsCount := streamsPerTenant * blocksPerStream * rowsPerBlock
 			if n := rowsCountTotal.Load(); n != uint32(expectedRowsCount) {
@@ -145,10 +146,10 @@ func TestStorageRunQuery(t *testing.T) {
 	t.Run("matching-multiple-tenant-ids", func(t *testing.T) {
 		q := mustParseQuery(`"log message"`)
 		var rowsCountTotal atomic.Uint32
-		processBlock := func(_ uint, rowsCount int, _ []BlockColumn) {
-			rowsCountTotal.Add(uint32(rowsCount))
+		writeBlock := func(_ uint, timestamps []int64, _ []BlockColumn) {
+			rowsCountTotal.Add(uint32(len(timestamps)))
 		}
-		s.RunQuery(allTenantIDs, q, nil, processBlock)
+		s.RunQuery(context.Background(), allTenantIDs, q, writeBlock)
 
 		expectedRowsCount := tenantsCount * streamsPerTenant * blocksPerStream * rowsPerBlock
 		if n := rowsCountTotal.Load(); n != uint32(expectedRowsCount) {
@@ -158,10 +159,10 @@ func TestStorageRunQuery(t *testing.T) {
 	t.Run("matching-in-filter", func(t *testing.T) {
 		q := mustParseQuery(`source-file:in(foobar,/foo/bar/baz)`)
 		var rowsCountTotal atomic.Uint32
-		processBlock := func(_ uint, rowsCount int, _ []BlockColumn) {
-			rowsCountTotal.Add(uint32(rowsCount))
+		writeBlock := func(_ uint, timestamps []int64, _ []BlockColumn) {
+			rowsCountTotal.Add(uint32(len(timestamps)))
 		}
-		s.RunQuery(allTenantIDs, q, nil, processBlock)
+		s.RunQuery(context.Background(), allTenantIDs, q, writeBlock)
 
 		expectedRowsCount := tenantsCount * streamsPerTenant * blocksPerStream * rowsPerBlock
 		if n := rowsCountTotal.Load(); n != uint32(expectedRowsCount) {
@@ -170,10 +171,10 @@ func TestStorageRunQuery(t *testing.T) {
 	})
 	t.Run("stream-filter-mismatch", func(_ *testing.T) {
 		q := mustParseQuery(`_stream:{job="foobar",instance=~"host-.+:2345"} log`)
-		processBlock := func(_ uint, rowsCount int, _ []BlockColumn) {
-			panic(fmt.Errorf("unexpected match for %d rows", rowsCount))
+		writeBlock := func(_ uint, timestamps []int64, _ []BlockColumn) {
+			panic(fmt.Errorf("unexpected match for %d rows", len(timestamps)))
 		}
-		s.RunQuery(allTenantIDs, q, nil, processBlock)
+		s.RunQuery(context.Background(), allTenantIDs, q, writeBlock)
 	})
 	t.Run("matching-stream-id", func(t *testing.T) {
 		for i := 0; i < streamsPerTenant; i++ {
@@ -184,14 +185,14 @@ func TestStorageRunQuery(t *testing.T) {
 			}
 			expectedStreamID := fmt.Sprintf("stream_id=%d", i)
 			var rowsCountTotal atomic.Uint32
-			processBlock := func(_ uint, rowsCount int, columns []BlockColumn) {
+			writeBlock := func(_ uint, timestamps []int64, columns []BlockColumn) {
 				hasStreamIDColumn := false
 				var columnNames []string
 				for _, c := range columns {
 					if c.Name == "stream-id" {
 						hasStreamIDColumn = true
-						if len(c.Values) != rowsCount {
-							panic(fmt.Errorf("unexpected number of rows for column %q; got %d; want %d", c.Name, len(c.Values), rowsCount))
+						if len(c.Values) != len(timestamps) {
+							panic(fmt.Errorf("unexpected number of rows for column %q; got %d; want %d", c.Name, len(c.Values), len(timestamps)))
 						}
 						for _, v := range c.Values {
 							if v != expectedStreamID {
@@ -204,10 +205,10 @@ func TestStorageRunQuery(t *testing.T) {
 				if !hasStreamIDColumn {
 					panic(fmt.Errorf("missing stream-id column among columns: %q", columnNames))
 				}
-				rowsCountTotal.Add(uint32(len(columns[0].Values)))
+				rowsCountTotal.Add(uint32(len(timestamps)))
 			}
 			tenantIDs := []TenantID{tenantID}
-			s.RunQuery(tenantIDs, q, nil, processBlock)
+			s.RunQuery(context.Background(), tenantIDs, q, writeBlock)
 
 			expectedRowsCount := blocksPerStream * rowsPerBlock
 			if n := rowsCountTotal.Load(); n != uint32(expectedRowsCount) {
@@ -222,11 +223,11 @@ func TestStorageRunQuery(t *testing.T) {
 			ProjectID: 11,
 		}
 		var rowsCountTotal atomic.Uint32
-		processBlock := func(_ uint, rowsCount int, _ []BlockColumn) {
-			rowsCountTotal.Add(uint32(rowsCount))
+		writeBlock := func(_ uint, timestamps []int64, _ []BlockColumn) {
+			rowsCountTotal.Add(uint32(len(timestamps)))
 		}
 		tenantIDs := []TenantID{tenantID}
-		s.RunQuery(tenantIDs, q, nil, processBlock)
+		s.RunQuery(context.Background(), tenantIDs, q, writeBlock)
 
 		expectedRowsCount := streamsPerTenant * blocksPerStream * 2
 		if n := rowsCountTotal.Load(); n != uint32(expectedRowsCount) {
@@ -242,11 +243,11 @@ func TestStorageRunQuery(t *testing.T) {
 			ProjectID: 11,
 		}
 		var rowsCountTotal atomic.Uint32
-		processBlock := func(_ uint, rowsCount int, _ []BlockColumn) {
-			rowsCountTotal.Add(uint32(rowsCount))
+		writeBlock := func(_ uint, timestamps []int64, _ []BlockColumn) {
+			rowsCountTotal.Add(uint32(len(timestamps)))
 		}
 		tenantIDs := []TenantID{tenantID}
-		s.RunQuery(tenantIDs, q, nil, processBlock)
+		s.RunQuery(context.Background(), tenantIDs, q, writeBlock)
 
 		expectedRowsCount := streamsPerTenant * blocksPerStream
 		if n := rowsCountTotal.Load(); n != uint32(expectedRowsCount) {
@@ -262,11 +263,11 @@ func TestStorageRunQuery(t *testing.T) {
 			ProjectID: 11,
 		}
 		var rowsCountTotal atomic.Uint32
-		processBlock := func(_ uint, rowsCount int, _ []BlockColumn) {
-			rowsCountTotal.Add(uint32(rowsCount))
+		writeBlock := func(_ uint, timestamps []int64, _ []BlockColumn) {
+			rowsCountTotal.Add(uint32(len(timestamps)))
 		}
 		tenantIDs := []TenantID{tenantID}
-		s.RunQuery(tenantIDs, q, nil, processBlock)
+		s.RunQuery(context.Background(), tenantIDs, q, writeBlock)
 
 		expectedRowsCount := blocksPerStream
 		if n := rowsCountTotal.Load(); n != uint32(expectedRowsCount) {
@@ -281,11 +282,11 @@ func TestStorageRunQuery(t *testing.T) {
 			AccountID: 1,
 			ProjectID: 11,
 		}
-		processBlock := func(_ uint, rowsCount int, _ []BlockColumn) {
-			panic(fmt.Errorf("unexpected match for %d rows", rowsCount))
+		writeBlock := func(_ uint, timestamps []int64, _ []BlockColumn) {
+			panic(fmt.Errorf("unexpected match for %d rows", len(timestamps)))
 		}
 		tenantIDs := []TenantID{tenantID}
-		s.RunQuery(tenantIDs, q, nil, processBlock)
+		s.RunQuery(context.Background(), tenantIDs, q, writeBlock)
 	})
 	t.Run("missing-time-range", func(_ *testing.T) {
 		minTimestamp := baseTimestamp + (rowsPerBlock+1)*1e9
@@ -295,11 +296,11 @@ func TestStorageRunQuery(t *testing.T) {
 			AccountID: 1,
 			ProjectID: 11,
 		}
-		processBlock := func(_ uint, rowsCount int, _ []BlockColumn) {
-			panic(fmt.Errorf("unexpected match for %d rows", rowsCount))
+		writeBlock := func(_ uint, timestamps []int64, _ []BlockColumn) {
+			panic(fmt.Errorf("unexpected match for %d rows", len(timestamps)))
 		}
 		tenantIDs := []TenantID{tenantID}
-		s.RunQuery(tenantIDs, q, nil, processBlock)
+		s.RunQuery(context.Background(), tenantIDs, q, writeBlock)
 	})
 
 	// Close the storage and delete its data