Netware amount of free space reported

I support a LAN with a Netware 4.11 server and Windows 98 workstations. When I add or delete files to or from the Netware volume, the amount of free space reported by Windows, Dos, or Netware does not seem to change much. Is ther a time lag or something I need to do for the change in the amount of free space to show up? What is the most accurate way to monitor the amount of free space left on the Netware volume? Thanks.