I use sphinx search engine for indexing about 22M records that is read from oracle with ODBC. The speed of indexing is not bad but after that indexing and sorting is completed, indexer hangs several minutes. I also used ranged query and nothing changed that was a little effective but the problem is still there.
I want to know what's going on behind the scenes in this time and how can I reduce that?
To see what's going on behind the scenes run indexer with --print-queries, if it doesn't help review database log and running queries at the moment when indexer seems to be hanging.