AEM slow down when copy node

Hi,

     Programatically,I am copy some nodes(source node) and paste it on under parent node(destination node).When this process executing AEM consume more cpu usage its nearly goes 90% so AEM Slow down.

Code

          import javax.jcr.Session;

          import javax.jcr.Workspace;

          import org.apache.sling.jcr.api.SlingRepository;

          .

          /**************Some Code**************/

               Session session = repository.loginAdministrative(null);

               Workspace ws = session.getWorkspace();

               ws.copy(sourceNodepath, ParentNodepath);

          /***********Some Code****************/

Thanx