Segments info: the files of the index
An index is stored as a set of files called segments. New documents go into new small segments, and Solr merges small segments into bigger ones over time. The Segments info tab lists them.
01 · The columns
- Segment: its name.
- Docs and Deleted: the documents in it, and the deleted ones it still holds.
- Size: the space it takes on disk.
- Created: when it was written.
- Source: flush for new documents, merge for a segment made from smaller ones.
- Lucene: the version that wrote it.
- Merge candidate: yes for segments Solr would merge next.
02 · What to look at
- Many deleted documents take disk space and slow searches a little. Optimize merges the segments and drops them.
- A new index, or one that was just emptied, has no segments: the tab says so.
- On very old Solr versions the list is not available, and the tab says so.