I'm slowly working my way through Ceph's features... I recently happened upon object maps. (I had heard of LevelDB being in there but never saw how to use it: That's because I have been using Python! And the Python library is missing lots of features! Grrr.) How fast are those omap calls? Which is faster: a single LevelDB query yielding a few bytes vs. a single RADOS object read of that many bytes at a specific offset? How about iterating through a whole set of values vs. reading a RADOS object holding the same amount of data? Thanks, -kb, the Kent who is guessing LevelDB will be slower in both cases, because he really isn't using the key/value aspect of LevelDB but is still paying for it.
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