On Tue, Sep 30, 2014 at 5:23 PM, Plato Zhang <sangongs@xxxxxxxxx> wrote: > 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? FYI: directory fragments in MDS satisfy all above requirement. but the code is not general enough to be used outside MDS > 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 -- 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
