diff --git a/pkg/parquetquery/predicates.go b/pkg/parquetquery/predicates.go
index f5b78edd556..e6e126fb644 100644
--- a/pkg/parquetquery/predicates.go
+++ b/pkg/parquetquery/predicates.go
@@ -133,29 +133,30 @@ func (p *regexPredicate) keep(v *pq.Value) bool {
 		return false
 	}
 
-	s := v.String()
-	if matched, ok := p.matches[s]; ok {
+	b := v.ByteArray()
+
+	// Check uses zero alloc optimization of map[string([]byte)]
+	if matched, ok := p.matches[string(b)]; ok {
 		return matched
 	}
 
 	matched := false
 	for _, r := range p.regs {
-		if r.MatchString(s) == p.shouldMatch {
+		if r.Match(b) == p.shouldMatch {
 			matched = true
 			break
 		}
 	}
 
-	p.matches[s] = matched
+	// Only alloc the string when updating the map
+	p.matches[string(b)] = matched
+
 	return matched
 }
 
 func (p *regexPredicate) KeepColumnChunk(cc pq.ColumnChunk) bool {
 	p.helper.setNewRowGroup()
 
-	// Reset match cache on each row group change
-	p.matches = make(map[string]bool, len(p.matches))
-
 	// Can we do any filtering here?
 	return true
 }
@@ -165,6 +166,20 @@ func (p *regexPredicate) KeepValue(v pq.Value) bool {
 }
 
 func (p *regexPredicate) KeepPage(page pq.Page) bool {
+	if p.helper.newRowGroup {
+		// Reset match cache on each row group change
+		// We delay until the first page is received
+		// so we can get an accurate count of the number
+		// of distinct values for dictionary columns.
+		count := len(p.matches)
+		if d := page.Dictionary(); d != nil {
+			if d.Len() > count {
+				count = d.Len()
+			}
+		}
+		p.matches = make(map[string]bool, count)
+	}
+
 	return p.helper.keepPage(page, p.KeepValue)
 }
 
diff --git a/tempodb/encoding/vparquet2/block_traceql_test.go b/tempodb/encoding/vparquet2/block_traceql_test.go
index 0fbb58b5d10..e36e33c27f4 100644
--- a/tempodb/encoding/vparquet2/block_traceql_test.go
+++ b/tempodb/encoding/vparquet2/block_traceql_test.go
@@ -456,6 +456,8 @@ func BenchmarkBackendBlockTraceQL(b *testing.B) {
 		{"spanAttValMatch", traceql.MustExtractFetchSpansRequest("{ span.bloom > 0 }")},
 		{"spanAttIntrinsicNoMatch", traceql.MustExtractFetchSpansRequest("{ name = `asdfasdf` }")},
 		{"spanAttIntrinsicMatch", traceql.MustExtractFetchSpansRequest("{ name = `gcs.ReadRange` }")},
+		{"spanAttIntrinsicRegexNoMatch", traceql.MustExtractFetchSpansRequest("{ name =~ `asdfasdf` }")},
+		{"spanAttIntrinsicRegexMatch", traceql.MustExtractFetchSpansRequest("{ name =~ `gcs.ReadRange` }")},
 
 		// resource
 		{"resourceAttNameNoMatch", traceql.MustExtractFetchSpansRequest("{ resource.foo = `bar` }")},
@@ -474,10 +476,10 @@ func BenchmarkBackendBlockTraceQL(b *testing.B) {
 
 	ctx := context.TODO()
 	tenantID := "1"
-	blockID := uuid.MustParse("149e41d2-cc4d-4f71-b355-3377eabc94c8")
+	blockID := uuid.MustParse("2968a567-5873-4e4c-b3cb-21c106c6714b")
 
 	r, _, _, err := local.New(&local.Config{
-		Path: path.Join("/home/joe/testblock/"),
+		Path: path.Join("/Users/marty/src/tmp/"),
 	})
 	require.NoError(b, err)