sightly data-sly-resource to include rendering result of content page

Hi , 

  I'm trying to include rendering result of a content page in sightly uing data-sly-resource tag like below 

 <article data-sly-resource"${contentpagepath/jcr:content/par.html}"
             data-sly-unwrap></article>

 With the above i'm able to see the result of the content page but it is taking ages to load the result . If the same page path i execute from a browser , like from browser if i execute http://localhost:4502/contentpagepath/jcr:content/par.html i can see the result in a second . 

Is using data-sly-resource right in my case ? Any pointers greately appreciated .