On Dec 7, 2011, at 13:20 , Shawn Heisey wrote: > On 12/6/2011 2:06 PM, Erik Hatcher wrote: >> I think the best thing that you could do here would be to lock in a version >> of Lucene (all the Lucene libraries) that you use with SolrCloud. Certainly >> not out of the realm of possibilities of some upcoming SolrCloud capability >> that requires some upgrading of Lucene though, but you may be set for a >> little while at least. > > I have no weight with the Lucene project, especially because I know very > little of its internals. > > If the code that handles each new index format were also able to read the > index format that preceded it, one could incrementally step forward from > revision to revision within trunk, running an optimize (forcedMerge?) at each > version to upgrade the index format.
Shawn - that is the case with Lucene. The issue Jamie is bringing up is going from an *unreleased* snapshot of Lucene to a later *unreleased* snapshot of Lucene - and those types of guarantees aren't made across snapshots like this.
