On Wednesday, October 15, 2014 8:28:05 AM UTC-5, Terry Brown wrote: > I don't think the post-scan does require Bob's always incrementing timestamp fix, I think the post-scan is a more general solution which addresses the ".leo files from other sources" aspect of the duplicated gnx problem, as well as the "loading the same file twice in one second" aspect of the problem fixed by Bob.
I just don't see how collisions can happen except in automated situations. The gnx contains the committer id plus a timestamp. That combination *is* going to be unique in general, unless the timestamps collide, which isn't going to happen except in Bob's case. > So for maximum code cleanliness Bob's fix could be removed. Again, I don't see how that statement can be correct. Each invocation of Leo must be based on a unique timestamp. > It seems that collecting the maximum index value for the gnx timestamp for a particular c /could/ be done in one of the existing scans, and that that seems like a less invasive fix than changing the gnx format. Less visible externally, but I really don't like it. And no, existing scans aren't up to the job because they happen too early, before we know what gnx's have been read. > Also, I'm not convinced any non-scan based solutions (other than a significant number of random bits) can really guarantee no collisions. The ".leo files from other sources" case basically means you have no idea what gnxs lurk in the file, unless you look. If that were true, Leo would have been fundamentally broken all these many years. But no, the combination of id and timestamp is almost always unique. We must not *ever* reassign gnx's, so any scheme that guarantees no *new* collisions will suffice. That's what uuids or file numbers do. Edward -- You received this message because you are subscribed to the Google Groups "leo-editor" group. To unsubscribe from this group and stop receiving emails from it, send an email to leo-editor+unsubscr...@googlegroups.com. To post to this group, send email to leo-editor@googlegroups.com. Visit this group at http://groups.google.com/group/leo-editor. For more options, visit https://groups.google.com/d/optout.
