Disk Space consuming more under session folder in Data.

Hi

Disk space is consuming more in directory: Program Files (x86)\SAP BusinessObjects\SAP BusinessObjects Enterprise XI 4.0\Data\Note1WIPS\sessions and few session we can see PDF and few session are xml docs.

Installed version : 4.2 SP5 Patch 2

Cluster : Environment.

DB: Oracle and Disk available space: 60GB and filling more than 50GB.

Any idea? how to what is these files and how to get out of this.