After running "delete by query ", disk space did not released.
What should I do to make disk space release?
That is a soft delete, it marks files as deleted but they still take space.
If you want to clean up space, you can use forcemerge which frees up the space used by deleted documents.
Forcemerge is resource intensive, you can use max_num_segments of 1 to fully merge it into 1 segment based on the index size. There is also the only_expunge_deletes option too.
Reference: Force merge API | Elasticsearch Guide [8.7] | Elastic