Add rbf.SyncEnabled

rbf/db.go

@@ -302,7 +302,7 @@ func (db *DB) checkpoint(exclusive bool, mu sync.Locker) error {
 	}
 
 	// Ensure WAL pages are fully copied & synced to DB file.
-	if err := db.file.Sync(); err != nil {
+	if err := fsync(db.file); err != nil {
 		return fmt.Errorf("db file sync: %w", err)
 	}
 

rbf/rbf.go

@@ -91,6 +91,11 @@ var (
 // Debug is just a temporary flag used for debugging.
 var Debug bool
 
+// Testing constants.
+const (
+	SyncEnabled = true
+)
+
 // Magic32 returns the magic bytes as a big endian encoded uint32.
 func Magic32() uint32 {
 	return binary.BigEndian.Uint32([]byte(Magic))
@@ -659,8 +664,15 @@ func truncate(path string, sz int64) error {
 
 	if err := f.Truncate(sz); err != nil {
 		return fmt.Errorf("truncate: %w", err)
-	} else if err := f.Sync(); err != nil {
+	} else if err := fsync(f); err != nil {
 		return fmt.Errorf("sync: %w", err)
 	}
 	return f.Close()
 }
+
+func fsync(f *os.File) error {
+	if !SyncEnabled {
+		return nil
+	}
+	return f.Sync()
+}

rbf/tx.go

@@ -1610,7 +1610,7 @@ func (tx *Tx) flushWALWriter() error {
 	// Flush cache to writer.
 	if _, err := w.WriteAt(tx.wcache, int64(segment.PageN)*PageSize); err != nil {
 		return fmt.Errorf("write wal segment: %w", err)
-	} else if err := w.Sync(); err != nil {
+	} else if err := fsync(w); err != nil {
 		return fmt.Errorf("sync wal segment: %w", err)
 	} else if err := w.Close(); err != nil {
 		return fmt.Errorf("close wal segment: %w", err)