I guess it should be something like sam designed in CDS(https://wiki.ceph.com/Planning/Blueprints/Infernalis/osd%3A_Tiering_II_(Warm-%3ECold)) On Wed, May 27, 2015 at 4:39 PM, Marcel Lauhoff <ml@xxxxxxxx> wrote: > Hi, > > I wrote a prototype for an OSD-based object stub feature. An object stub > being an object with it's data moved /elsewhere/. I hope to get some > feedback, especially whether I'm on the right path here and if it > is a feature you are interested in. > > > > Code is in my "osd-stubs" branch: > https://github.com/ceph/ceph/compare/master...irq0:osd-stubs > https://github.com/irq0/ceph/tree/osd-stubs > > Tools to toy around with osd-stubs + web server to send stubs to: > https://github.com/irq0/ceph_osd-stub_tools > > > > Related: > - https://wiki.ceph.com/Planning/Blueprints/%3CSIDEBOARD%3E/osd:_tiering:_object_redirects > > > > Implementation: > > Adds two new OSD OPs: > - STUB :: Move data away; Save location in xattr; Set > object_info_t::stub_state to 'remote' > - UNSTUB :: Get data back; Remove xattr; Set object_info_t::stub_state > to 'local' > > > STUB is meant to be called by an external archive agent. UNSTUB > implicitly when OPs come in that need the object's data. Operations are > classified as "may_use_obj_data" similar to how op->may_{write,read,cache} work. > > The implicit UNSUB is implemented by prepending an UNSTUB operation to the > incoming OP list if "may_use_obj_data() and stub_state == REMOTE". > This sadly causes a waring in the client saying that > the reply doesn't match the request. He is of course right, but I found > it to be the simplest way to try that feature. > > External storage in the prototype is just simple HTTP: PUT on STUB; > GET+DELETE on UNSTUB. > > The Operations implement a kind of converter: STUB reads from the > primary OSD, store the object on the remote and then issue TRUNCATE(0) > and SETXATTR OPs. Similar UNSTUB retrieves the object, then does > WRITEFULL and RMXATTR. > > > ~marcel > > -- > Marcel Lauhoff > Mail/XMPP: ml@xxxxxxxx > http://irq0.org > -- > 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 -- Best Regards, Wheat -- 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
