Question / Problem
Why does TreeSize show charts on the "History" tab going back a long time in the past for some volumes, and empty charts for others?
Answer / Solution
For each scan that is executed on a specific folder or drive, TreeSize automatically saves the size from that scan for the use in the "History" view. If another scan on that same folder is done, TreeSize will add the new size data and create a graphical trend for this folder. This is the reason why you might see different periods of time for different drives and/or folders.
We have another product named SpaceObServer, which is much more powerful in regards to creating reliable statistics for the increase/decrease and the historic developement of disk usage of your systems. SpaceObServer scans local and network drives as well as Exchange mailboxes and Linux/Unix-servers via SSH using a background service and stores their structure, sizes and properties in an SQL database.
In a user interface similar to TreeSize the collected data can be viewed and browsed in hierarchical or tabular views, 3D bar, pie, line charts and tree maps. Using the archived data you are able to track the development of the space usage from past to present, and forecast future size usage.