On Tue, 2009-08-18 at 17:36 +0200, Maciej Piechotka wrote: [CUT]
> Hmm. Is it one-in-all database? Then: > - How you keep it out of corruption. Hardware and software errors > happens and sometimes one lost files. If it is one file - ok I can live > with it. If it is one-in-all file - ops (and please note that average > user does not make backup). We have something in mind for this where we'll have a automatic periodically made backup of all of the user's data, plus a journal of not yet backupped such data. This indeed means redundantly storing, but the redundant store ensures that data-loss is virtually impossible (only when both databases get corrupted simultaneously). For that last rather unlikely event, we'll also have normal backup features. The format of that backup will be Turtle, which is a humanly readable w3 standardized format for storing RDF triples. We have also plans to separate indexable data from user unique data, and store the two kinds of datas in different locations (.cache and .local). > - Some fs makes operations with small files much more efficient then > bigger (reiser* for example). It may have performance impact. We use sqlite which has its own internal performance optimizations that work mostly unaffected by such FS specifics. The FS can of course always have an influence. Use a FS that makes sense, if it does (many apps use sqlite nowadays, any FS that disses sqlite is going to perform badly for a lot of desktop applications. Including Firefox and Evolution, for example). > - What with concurrent access? Currently we give priority to read queries and we queue write queries. Read queries are always solved immediately. We don't yet support having two concurrently running read queries (we want to avoid usage threads in tracker-store as much as possible, everything happens on the GMainLoop at this moment). It's not decided that this wont ever change. The Turtle format: http://www.w3.org/TeamSubmission/turtle/ -- Philip Van Hoof, freelance software developer home: me at pvanhoof dot be gnome: pvanhoof at gnome dot org http://pvanhoof.be/blog http://codeminded.be _______________________________________________ desktop-devel-list mailing list [email protected] http://mail.gnome.org/mailman/listinfo/desktop-devel-list
