Hi Sage, I've created "PG/ReplicatedPG API" ( http://tracker.ceph.com/issues/4928 ) for the first action item: > - clean up the OSD -> PG interface and started with IPG class to be used in place of PG/ReplicatedPG ( https://github.com/dachary/ceph/commit/66d798753fc90e0daa7d8ce92ef7b692e259484f ). I'll join the standup tomorrow ( past two days were hollidays in France ;-) Cheers On 05/09/2013 05:23 PM, Sage Weil wrote: > We have a great session with Loic, Christopher, Sam, and Greg that > discussed how to move forward with erasure coding support. The high-level > consensus on approach: > > - it is possible to do erasure coding above rados across distinct pools, > but it is harder, and less useful. > - we should have an ErasureCodedPG that takes advantage of CRUSH's > placement to place shards > - we can support a limited subset of rados operations for such pools and > still be useful (write_full, or write/append on block boundaries) > - this will be used in conjuction with a replicated pool as a second tier > of storage, or by applications that are happy with a limited subset of > commands. > > That said, the implementation will be non-trivial. But, we identified > several areas where code cleanup will move us down the right path. By > factoring our useful components of PG and ReplicatedPG into separate > classes, we clean up the current interfaces and can also build unit tests > for them as we do so for immediate benefit. > > Initial focus areas: > > - clean up the OSD -> PG interface (PG -> OSD is already reasonably well > captured by teh OSDService class) > - ObjectContext tracking > - PG log handling > - PG missing > - RepOp state > - Peering state machine > > The last one willb e most tricky (and saved for last). In each case, > we'll have to think carefully about how well things generalize from > replication to erasure coding. > > Loic has volunteered to own this work, and Sam and I will be supporting. > He'll also be joining our daily core standup. Yay! > > sage > -- > 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 -- Loïc Dachary, Artisan Logiciel Libre All that is necessary for the triumph of evil is that good people do nothing.
Attachment:
signature.asc
Description: OpenPGP digital signature
