items = [ {id:1, value:3, perc:0.5}, {id:2, value:2, perc:0.3}, {id:3, value:1, perc:0.2} ]
items.sort(function (a, b){
    return (b.value - a.value)
})

Ordenar ascendentemente por perc
items.sort(function (a, b) {
    return (a.perc - b.perc)
})