presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/storage/FileStorageService.java/FileStorageService/deleteStagingFilesAsync
class FileStorageService:    private void deleteStagingFilesAsync()
    {
        List<File> files = listFiles(baseStagingDir, null);
        if (!files.isEmpty()) {
            new Thread(() -> {
                for (File file : files) {
                    try {
                        Files.deleteIfExists(file.toPath());
                    }
                    catch (IOException e) {
                        log.warn(e, "Failed to delete file: %s", file.getAbsolutePath());
                    }
                }
            }, "background-staging-delete").start();
        }
    }