During a recent VOB restore I performed, I noticed that the VOB storage pool (the sdft subfolder) contains several large files, prefixed with tmp_ (for example, myvob.vbs/s/sdft/10/1d/tmp_3996.1)
Turns out these are called ‘unreferenced containers’, or ‘debris’.
In order to get rid of those, one should use the checkvob command. Login to the VOB servrer as the VOB owner or ClearCase admin, start a view, and run the following:
cleartool checkvob -force -fix -debris -pool -source <path to VOB storage>
This will removed all unreferenced containers to the ‘lost+found’ subfolder of the source pool. You can then delete them from the pool’s lost+found folder, after making sure everything works as expected.