add attribute partialSubmit="true/false" to f:ajax and
parameter partialSubmit:'true/false' to jsf.ajax.request options
Only the components named in the "execute" parameter are processed in phase 2-4,
but the spec insists on submitting all elements included in a form. If
partialSubmit is set to true submission is reduced to the form params named in
execute. This is a performance feature that can boost speed on large pages.