CommandButton execution while rendering

Question: How can I prevent the execution of a while the website is rendering?

Thats where my Button sits:

<p:dialog widgetVar="newComment" height="200" width="500">
    <h:form>
        <h:panelGrid>
            <h:outputText value="#{commentDialog.username}" />
            <h:inputTextarea id="in_text" value="#{commentDialog.text}" />
            <p:message for="in_text" />
        </h:panelGrid>
        <p:commandButton validateClient="true" value="Abschicken" ajax="true"
            actionListener="#{popupRequestView.update}" action="PF('newComment').hide();update_popup();" />
    </h:form>
</p:dialog>