Using Virtuoso 6.1.1, I loaded a database containing about 500 million triples (and a fair amount of text). After loading, the on-disk database had expanded to about 67G of storage. Conductor reported that I had about 26G -free- in that database. (I'm not sure exactly why that extra space was needed during the load, but it is perhaps the result of a computation we run as part of loading that creates and drops a number of temporary graphs.)
Since it would be handy to recover that 26G of disk space for other purposes, I did a full backup followed by a restore into a fresh Virtuoso. I was suprised to find that the restored database was still 67G on disk with 26G of free space. I seem to recall using backup/restore to reclaim free space several releases ago, and it worked. Is my memory failing me? In any case, is there any way to get Virtuoso to let me have those 26G back? Or is that space not "free" in that sense of the word? (I went looking for tools that claimed to be able to "clean up" the database in any sense, but the only thing I found was DB.DBA.VACUUM(), which does not help.) -- Alan Bawden [email protected]
