* I believe the NRT patches are included in the 4.x trunk. I don't think there's any support as yet in 3x (uses features in Lucene 3.0).
* For merging, I'm talking about commits/writes. If you merge while commits are going on, things can get a bit messy (maybe on source cores this is ok, but I have a feeling it's not). * For moving data to a an 'offline' read-only core, this is the trickiest bit. We do this today by using a round-robin chain of remote shards and 2 local cores. At the boundary time (e.g. 1 day), the 'active' core is replicated locally, then this local replica is replicated to the next shard in the chain. Once everything is complete, the local replica is discarded, and the 'active' core is cleaned, being careful not to delete any new data since the replicated commit point. It's not the easiest thing to implement, but boy it scales forever! Peter
