koa-static-cache源码 使用了fs.readFileSync 来读取文件， 这个不会阻塞cpu吗？

      源码
	  
function loadFile(name, dir, options, files) {
    ....
    var stats = fs.statSync(filename)
    var buffer = fs.readFileSync(filename)

    obj.cacheControl = options.cacheControl
    obj.maxAge = obj.maxAge ? obj.maxAge : options.maxAge || 0
    obj.type = obj.mime = mime.lookup(pathname) || 'application/octet-stream'
    obj.mtime = stats.mtime
    obj.length = stats.size
    obj.md5 = crypto.createHash('md5').update(buffer).digest('base64')

    debug('file: ' + JSON.stringify(obj, null, 2))
    if (options.buffer)
        obj.buffer = buffer

    buffer = null
    return obj
}
```end

求解