MatchVersionedFile: speed (#19522)

<img width="2054" height="328" alt="Screenshot 2026-02-27 at 16 07 01"
src="https://github.com/user-attachments/assets/37bfc853-bccb-4083-a494-8c989e06ca08"
/>

Author: AskAlexSharov

db/version/file_version.go

@@ -229,19 +229,36 @@ func MatchVersionedFile(filePattern string, dirEntries []string, dir string) (st
 	var bestVersion Version
 	found := false
 
-	for _, name := range dirEntries {
-		matched, err := filepath.Match(filePattern, name)
-		if err != nil {
-			return "", Version{}, false, fmt.Errorf("invalid pattern: %w", err)
-		}
-		if matched {
+	// Optimization: patterns like "*-accounts.0-1.kv" are common — a single leading wildcard
+	// followed by a literal suffix. Use HasSuffix instead of filepath.Match (which is ~50x slower).
+	if strings.HasPrefix(filePattern, "*") && !strings.ContainsAny(filePattern[1:], "*?[") {
+		suffix := filePattern[1:]
+		for _, name := range dirEntries {
+			if !strings.HasSuffix(name, suffix) {
+				continue
+			}
 			ver, _ := ParseVersion(name)
 			if !found || ver.Greater(bestVersion) {
 				bestVersion = ver
 				bestMatch = name
 				found = true
 			}
 		}
+	} else {
+		for _, name := range dirEntries {
+			matched, err := filepath.Match(filePattern, name)
+			if err != nil {
+				return "", Version{}, false, fmt.Errorf("invalid pattern: %w", err)
+			}
+			if matched {
+				ver, _ := ParseVersion(name)
+				if !found || ver.Greater(bestVersion) {
+					bestVersion = ver
+					bestMatch = name
+					found = true
+				}
+			}
+		}
 	}
 
 	if !found {

db/version/file_version_test.go

@@ -1,6 +1,7 @@
 package version
 
 import (
+	"fmt"
 	"os"
 	"path/filepath"
 	"reflect"
@@ -400,3 +401,21 @@ func TestMatchVersionedFile_DifferentSegAndIdxNames(t *testing.T) {
 		t.Fatal("expected ok == false for non-existent file type")
 	}
 }
+
+func BenchmarkMatchVersionedFile(b *testing.B) {
+	// Simulate a large directory with thousands of snapshot files (realistic scenario)
+	dirEntries := make([]string, 0, 2000)
+	for i := 0; i < 500; i++ {
+		dirEntries = append(dirEntries,
+			fmt.Sprintf("v1.0-accounts.%d-%d.kv", i, i+1),
+			fmt.Sprintf("v1.0-storage.%d-%d.kv", i, i+1),
+			fmt.Sprintf("v1.0-accounts.%d-%d.kvi", i, i+1),
+			fmt.Sprintf("v1.0-storage.%d-%d.kvi", i, i+1),
+		)
+	}
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		_, _, _, _ = MatchVersionedFile("*-accounts.0-1.kvi", dirEntries, "/tmp")
+	}
+}