HI Ivan, Thanks for the info... I'm currently considering a multi-tenent system setup where individual users will 'own' data stored in graphs. I wish to enforce a quota against each user. But it sounds like I may have to come up with some other strategy for restricting the amount of data a user can store...
Cheers Mark On 18 January 2011 19:12, Ivan Mikhailov <[email protected]> wrote: > Hello Mark, > > On Sun, 2011-01-16 at 14:21 +1100, Mark James wrote: > > > Is there an easy way to determine the amount of disk space an > > individual quad store graph is taking up? > > > Indexes for IRIs and literals are common for all graphs, so it's not > obvious how to count the consumed space if an IRI is used in more than > one graph. > Accounting for quads becomes unclear too. > Before version 6 it was possible at least to get the size of indexes for > quads, divide it by total number of quads in all graphs (to get a disk > cost of a single quad) and multiply by number of quads in the specified > graph, thus some adequate number was available. Starting from version 6, > there are partial indexes on S,P and O,P, as a part of "3+2" indexing > model, and data of these indexes are shared for all graphs, so not > counting is possible for same reason as for IRIs. In addition, indexes > become bitmaps with compression that can sometimes save significant > amounts of additional data "for free". > So I don't know what to recommend as a reasonable measurement method. > Existing real-life storages may give some hint, but not more, > experiments with synthetic data like benchmarks does not give even a > hint, because they're "too synthetic". > > Best Regards, > > Ivan Mikhailov > OpenLink Software > http://virtuoso.openlinksw.com > > >
