On Tue, Sep 20, 2011 at 2:08 AM, MORITA Kazutaka < morita.kazutaka at lab.ntt.co.jp> wrote: > At Mon, 19 Sep 2011 16:45:06 -0700, > Wenhao Xu wrote: > Hi Wenhao, > > Thanks for your interest! > > > > > Hi folks, > > > > I just started looking at the sheepdog project. I really like what you > are > > doing here and would like to contribute code in the near future. After > > reading the slides from kvm forum, I have the following questions: > > 1. How to determine the id for an object? E.g. for a data object inside a > > VDI, how to give it an ID? > > The object ID is a 64 bit integer. The upper 32 bit is a vdi ID, > which is calculated from a vdi name with a hash function. The lower > 32 bit is an index of the data object. Sheepdog splits a virtual disk > into 4 MB chunks (data objects), and the index is used for the lower > 32 bit. > > > 2. What is the relationship between vdi object and inode? How to locate > > them? Are they also located by using consistency hashing? > > Both are same. We should unify the names. Vdi objects are also > located with consistent hashing. > > > 3. Can each vdi volume have its own replication factor? > > Currently no, but it should have. > > > 4. How is the user_xattr is used? Why it is required by sheepdog? > > It is used to store some cluster informations (e.g. the creation time > of cluster). If possible, I'd like to remove the dependency. > > > 5. Corosync uses multicast to do communications. However, in data center, > > multicast may be disabled on the switch/router. Is it easy to replace > > corosync with another engine to manage the node membership, e.g. > zookeeper? > > I would be very happy to contribute on this part. > > I think it is not so difficult. We have a plan to introduce a cluster > driver which abstracts cluster management, and move all corosync > related codes to the driver. I think we can support zookeeper in the > driver. > > This sounds great. Is the cluster driver interface available now? Having a concept of cluster driver really helps. > Currently, my coworker is working on a new cordination system project > to become an alternative of corosync in Sheepdog. I guess he can > announce the project soon. > Great. Looking forward to hear more about it. > > Thanks, > > Kazutaka > Thanks for the reply, Kazutaka. Wenhao -- ~_~ -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.wpkg.org/pipermail/sheepdog/attachments/20110921/8dc7b1ca/attachment.html> |