The Derived Objects node displays disk storage used by shared derived objects in the VOB. A graph displays which views refer to shared DOs and shows how much disk space is used by the shared DOs that each view refers to.
You can use this information to identify views that should no longer refer to the DOs. Removing references to the DOs in those views can allow the disk space used by the DOs in the VOB to be reclaimed. When a DO no longer appears in any view, the scrubber utility, usually run as the Daily VOB Pool Scrubbing scheduled job, can remove the DO and its associated storage from the VOB.
This display uses previously generated data that has been cached on the VOB or view server host. This data is usually generated by the Daily VOB Space or Daily View Space scheduled job. If no data is available, you can use the ClearCase scheduler to run the job on the VOB or view server host.
The display is a bar graph with views along the X-axis and disk storage used by DOs along the Y-axis. For each view, the bar displays the disk space, in megabytes, used by DOs that the view refers to. Views are arranged left to right from greatest to least DO disk space used.
Each view bar is divided into two portions, one showing space used by DOs with reference counts of 1, the other showing space used by DOs with reference counts greater than 1. The reference count is the number of views in which a DO appears. Each time the DO is winked in to another view, its reference count is incremented. Each time the DO is deleted from a view, its reference count is decremented.
When you right-click a bar in the graph, a shortcut menu appears with the following command:
Properties of View: Opens a dialog box in which you can view or edit the view's general properties, config spec, access information, protections, advanced properties, and (for a snapshot view) load rules.
Clicking Options opens a dialog box where you can change aspects of the display: