mongoose 每次查询完是否需要手动断开连接呢？

Question

用的koa2，写在app.js中

mongoose.connect(dbConfig.dbs,{
  useNewUrlParser:true,
  server: {
    poolSize: 4,
    auto_reconnect: true
  }
})
const con = mongoose.connection;
con.on('open', () => {
  console.log('db open')
})
con.on('error', console.error.bind(console, '连接数据库失败'));
con.on('disconnected', () => {
  console.log('db disconnected')
})

之前用mysql是每次查询完之后手动断开连接或者配置连接池，
想问下mongoose是否也要配置连接池，或者每次进入路由连接，查询完再断开？
如下代码

router.get('/add', async (ctx, next) => {
  mongoose.connect() // 连接
  const aaa = new Test({
    name: ctx.query.name,
    age: ctx.query.age,
    list: ctx.query.list
  })

  let code

  try {
    await aaa.save()
    code = 0
  } catch (e) {
    code = e
  }
  mongoose.disconnect() // 断开
  ctx.body = {
    code
  }
})