Thanks Mike(s) & Co. Added https://issues.apache.org/jira/browse/LUCENE-5419
Sounds like a killer feature :) Otis On Wed, Jan 8, 2014 at 4:17 AM, Michael McCandless < luc...@mikemccandless.com> wrote: > On Mon, Jan 6, 2014 at 3:42 PM, Michael Sokolov > <msoko...@safaribooksonline.com> wrote: > > I think the key optimization when there are no deletions is that you > don't > > need to renumber documents and can bulk-copy blocks of contiguous > documents, > > and that is independent of merge policy. I think :) > > Merging of term vectors and stored fields will always use bulk-copy > for contiguous chunks of non-deleted docs, so for the append-only case > these will be the max chunk size and be efficient. > > We have no codec that implements bulk merging for postings, which > would be interesting to pursue: in the append-only case it's possible, > and merging of postings is normally by far the most time consuming > step of a merge. > > Also, no RAM will be used holding the doc mapping, since the docIDs > don't change. > > These benefits are independent of the MergePolicy. > > I think TieredMergePolicy will work fine for append-only; I'm not sure > how you'd improve on its approach. It will in general renumber the > docs, so if that's a problem, apps should use LogByteSizeMP. > > Mike McCandless > > http://blog.mikemccandless.com >
