Hi all, We plan to develop a new distributed key-value storage engine, which would based on rados and supoort range-scan operation. Besides, it'll be open source. We know rados is already a kv storage engine, and can do pretty well if we use KeyValueStore. However, it lacks the ability of scanning a key range, since keys are hashed into pgs. In our scenarios, scanning is a common need. We considered the way of splitting our key space into fixed number of ranges, mapping each range to a rados object, and then storing key/value pairs in rados objects. However, there are two main disadvantages: 1. We can not adjust the number of ranges as the cluster scales. 2. For a good splitting, we must properly predict the distribution of keys, or we'll encounter serious load-balance problem. So we decide to develop a new service based on rados (we want to use rados for unifying our storage infrastructure). Before we start, we want to do some inquiries: 1. Is there already any similar system/module(scan-supported && rados-based) existed? 2. Except for the basic key-value functions, what features are you most interested in? 3. Other suggestions? Thanks! -- 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
