On Sat, Nov 12, 2011 at 12:04:47AM +0800, Liu Yuan wrote: > I am not sure what is reflink. is it synonym to snapshot? IIC, yes, the > new storage infrastructure named 'farm' will support clsuter-wide snapshot. It basically is a file level snapshot, see here for an introduction: http://oss.oracle.com/osswiki/OCFS2/DesignDocs/ReflinkOperation > Simply put, it somewhat resembles git a lot (both code and idea level). > there are three object type, named 'data, trunk, snapshot' that is > similar to git's 'blob, tree, commit'. > > 'data' is just sheepdog's data object, only named by its sha1ed content. > So the data objects with the same content will be mapped to only single > sha1 name, thus achieve node-wide data sharing. > > 'snapshot' object will serve to support snapshot which contains the > snapshoted trunk, that is 'directory' of the that-time data objects on > each node. The trunk object will provide a means to find data objects. > This will support cluster-wide snapshot. > > The 'farm' doesn't has any constraint to object data size. Hope this helps. How well do snapshots / COW images work with large objects? Either way, I'm looking forward to see your work. |