https://swiftstack.com/blog/2012/11/21/how-the-ring-works-in-openstack-swift/ is soemthing that should be able to give you a pretty complete overview of how the ring works in Swift and how data placement works. Let me know if you have more questions after you watch that video. --John On Aug 19, 2014, at 5:34 PM, Brent Troge <brenttroge2016 at gmail.com> wrote: > > Excuse this question and for lack of basic understanding. I dropped from school at 8th grade, so everything is basically self taught. Here goes. > > I am trying to figure out where each offset/partition is placed on the ring. > > > So If I have 50 drives with a weight of 100 each I come up with the below part power > > part power = log2(50 * 100) = 13 > > Using that I then come up with the amount of partitions. > > partitions = 2^13 = 8192 > > Now here is where my ignorance comes into play. How do I use these datapoints to determine where each offset is on the ring? > > I then guess that for each offset they will have a fixed range of values that map to that partition. > > So for example, for offset 1, all object URL md5 hashes that have a decimal value of 0 through 100 will go here(i just made up the range 0 through 100, i have no idea what the range would be with respect to my given part-power, drive, etc). > _______________________________________________ > Mailing list: http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > Post to : openstack at lists.openstack.org > Unsubscribe : http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 801 bytes Desc: Message signed with OpenPGP using GPGMail URL: <http://lists.openstack.org/pipermail/openstack/attachments/20140819/d4df265f/attachment.sig>