Ember-data: handling temporary data with non-persistent relationships

gistfile1.js

{
  tops: [{
    hostname: "hostname",
    load: 10,
    processes: [{
      name: "ruby",
      RSS: 20000
    }]
  }]
}

/*
  This feels like we have the following models:

  host:
    hostname: string
    load: integer
    processes: hasMany 'process'

  process:
    name: string
    RSS: integer
    host: belongsTo 'host'

  But how do we link these up given that there are no ids?
  I could fake it (e.g. autoincrement when generating the data), but I'm wondering if there is another way?
*/