[2357] Server Render Page - log execute time

Hello! I use nuxt rc11 and use server express module

I need log execute time

I use this code

app.use(function (req, res, next) {
    console.log('req', req.url)

    nuxt.render(req, res, next)
})

But i want use this code

app.use(function (req, res, next) {
    console.log('req', req.url)

    var startExecute = new Date()

    nuxt.render(req, res, next)
        .then(r => {

            var endExecute = new Date()

            console.log('execute', endExecute - startExecute)
        })
})

But function nuxt.render() not return promise

Please help me!!!!