Hi Mike, Just want to mention if the user chooses to use single thread to index and use LogXXMergePolicy then the document order will be preserved as index order.
On Thu, May 4, 2023 at 10:04 AM Wei <weiwan...@gmail.com> wrote: > Hi Michael, > > We are interested in the segment sequence for early termination. In our > case there is always a large dominant segment after index rebuild, then > many small segments are generated with continuous updates as time goes by. > When early termination is applied, the limit could be reached just for > traversing the dominant segment alone and the newer smaller segments > doesn't get a chance. If we can control the segment sequence so that the > newer segments are visited first, the documents with recent updates can be > retrieved with early termination. Do you think this makes sense? Any > suggestion is appreciated. > > Thanks, > Wei > > On Thu, May 4, 2023 at 3:33 AM Michael Sokolov <msoko...@gmail.com> wrote: > > > There is no meaning to the sequence. The segments are created > concurrently > > by many threads and the merge process will merge them without regards to > > any ordering. > > > > > > > > On Wed, May 3, 2023, 1:09 PM Patrick Zhai <zhai7...@gmail.com> wrote: > > > > > For that part I'm not entirely sure, if other folks know it please > chime > > in > > > :) > > > > > > On Wed, May 3, 2023 at 8:48 AM Wei <weiwan...@gmail.com> wrote: > > > > > > > Thanks Patrick! In the default case when no LeafSorter is provided, > are > > > the > > > > segments traversed in the order of creation time, i.e. the oldest > > segment > > > > is always visited first? > > > > > > > > Wei > > > > > > > > On Tue, May 2, 2023 at 7:22 PM Patrick Zhai <zhai7...@gmail.com> > > wrote: > > > > > > > > > Hi Wei, > > > > > Lucene in general iterate through the index in the order of what is > > > > > recorded in the SegmentInfos > > > > > < > > > > > > > > > > > > > > > https://github.com/apache/lucene/blob/main/lucene/core/src/java/org/apache/lucene/index/SegmentInfos.java#L140 > > > > > > > > > > > And at search time, you can specify the order using LeafSorter > > > > > < > > > > > > > > > > > > > > > https://github.com/apache/lucene/blob/main/lucene/core/src/java/org/apache/lucene/index/DirectoryReader.java#L75 > > > > > > > > > > > when you're opening the IndexReader > > > > > > > > > > Patrick > > > > > > > > > > On Tue, May 2, 2023 at 5:28 PM Wei <weiwan...@gmail.com> wrote: > > > > > > > > > > > Hello, > > > > > > > > > > > > We have a index that has multiple segments generated with > > continuous > > > > > > updates. Does Lucene have a specific order when iterate through > > the > > > > > > segments (assuming single query thread) ? Can the order be > > customized > > > > > that > > > > > > the latest generated segments are searched first? > > > > > > > > > > > > Thanks, > > > > > > Wei > > > > > > > > > > > > > > > > > > > > >
