Node Js file upload : app frozen

I have a problem with my app (node js) and file upload. I make e simple form dans while a upload it, my app freeze when i load it in production mode (service with the node package :forever)

But if i run my app with the simple command line : npm start, all work fine.

Here is my code :

div(class='modal fade', id='add')
            div.modal-dialog
                div.modal-content
                    form(action='/upload', class='form-upload', enctype='multipart/form-data', method='post')
                        div.modal-header
                            button(type='button', class='close', data-dismiss='modal', aria-label='close')
                                span(aria-hidden='true',) ×
                            h4 
                                strong Ajouter un média
                        div.modal-body
                            .form-group
                                label(class='control-label') Position
                                input(type='text', name='order', class='form-control input-lg')
                            .form-group
                                label(class='control-label') Nom du fichier
                                input(type='text', name='name', class='form-control input-lg')
                            .form-group
                                label(class='control-label') Délai
                                input(type='text', name='delay', class='form-control input-lg')
                            .form-group
                                label(class='control-label') Fichier
                                input(type='file', name='upload', class='form-control input-lg')
                        div.modal-footer
                            button(type='button', class='btn btn-default', data-dismiss='modal') Fermer
                            button(type='submit', class='btn btn-primary') Enregistrer

Route :

// POST Upload
    router.post('/upload', isAuthenticated, function(req, res)
    {
        res.send('upload OK');

    });

And maybe interesting (user serialize and deserialize)

var login = require('./login');

module.exports = function(passport){

passport.serializeUser(function(user, done) {
  console.log("serializing " + user.username);
  done(null, user);
});

passport.deserializeUser(function(user, done) {
  console.log("deserializing " + user);
  done(null, user);
});

    login(passport);
}

Here is the log of my APP (it freeze on upload)

serializing raph
^[[0mGET /login/?access_token=123456789
deserializing [object Object]
^[[0mGET /dashboard ^[[32m200 ^[[0m785.797 ms - 7177^[[0m
deserializing [object Object]
^[[0mPOST /upload ^[[32m200 ^[[0m4.801 ms - 4^[[0m

Have someone an idea to hemp me to resolve this problem ?