The TEP workspaces do not show the server real-time data. There is a delay in the attributes it displays compared to real-time data on the server.
The ITM agent is not constantly querying the Tivoli Storage Manager servers to update the data. The agent will query the servers for different server attributes and update the DERBY database at intervals. What you see in the workspace is what is in the DERBY database. The workspace data is as current as of the last time the DERBY database was updated. You can check when the last time the DERBY database was updated from the agent log. For example,
Resolving the problem
The default interval is 30 minutes, meaning the DERBY database will get updated every 30 minutes with new data. This value can be modified to make it query the server more or less often. Visit the following page for different options you can set:
KSK_PREFETCH_MINUTES is the option in the question. However, please remember that the more often the server is queried, the greater the workload put on the ITM server and the TSM server. If an adverse affect is observed with the server performance, you may want to reduce the frequency of this query. There isn't really any good measure of how often you should query the server. It's a trial and error scenario, experimentation will be needed to determine what is best for your specific environment.