asp.net - stop background processing on reportviewer cancel -

i have web page user can select report parameters , when submit request im opening popup window report being generated of report viewer control.

when report still processing , user closes popupwindow , background processing still active, because of when click on link in main parent page taking lot of time load.when checked fiddler came know because of reportserver requests been processing in background causing issue.

i tried kept close button on popup page , on server side close click event im trying reset reportviewer, not stopping requests running in background.

below reset code didn't work

 protected sub btnclose_click(sender object, e eventargs) handles btnclose.click      rptviewer.reset()   end sub 

is there way dispose these background processing of requests.