On Mon, Apr 30, 2012 at 14:08, Sage Weil <sage@xxxxxxxxxxxx> wrote: >> Does just adding a .db suffix make the name safe? If yes, xattr is not >> needed; if no, it's not enough. Reading src/rados_export.cc and >> src/rados_sync.cc, I see nothing like that. What if I have objects >> "foo" and "foo.db" in a pool? > > I'm pretty sure we need to mark the object with a magic xattr. Which > probably means the filename itself needs to be mangled to avoid colliding > with other objects. Probably an xattr on the object file referring to the > external mangled file with the k/v content. Perhaps make the db file use one of the reserved characters that will never appear in a plain old rados object. $ is the only one that's really safe.. >> Note to self: the only thing avoiding collisions for e.g. "foo/" and >> "foo$" is the hash. > I vaguely recall Colin talking about the trailing /, but we may have > decided to ignore the problem for now. Oh I mean anything that gets mapped to @ can cause collisions. "foo@" and "foo$" will collide. "foo\n" and "foo\\" will collide. Frankly, my gut instinct right now is "kill it with fire". Collisions in object names is a miserable problem to have. This would have been better off with e.g. a HTTP-style %20 escaping mechanism, or a \x20 style one; one that preserves the byte, and does not just replace it with '@'. -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
