I moved a directory tree containing most of my indexed files. Updating the index almost doubled its size. Now there are 28.6 GB of index files under the directory xapiandb. At the end of the index update, while the status bar shows "Indexing in progress: Purge", the recoll process starts consuming all of the available memory until swapping to disk begins (recoll apparently needs more than 3 GB for purging my index). I tried to let it finish but eventually killed the recoll process after a few hours. Is there a way to purge the index without excessive memory usage?