[incremental indexing] - IndexUpdater.update_searcher is successful but search result does not show newly indexed passage

[jessiejuachon]

Test environment:

• Index size of ~ 12 GB created on a GPU
• IndexUpdater and Search on CPU

Steps to reproduce:

1. Initialize the Searcher, passing the index path pointing to the the 12 GB index. searcher = Searcher(checkpoint=self._checkpoint, index=self._index_path, collection=Collection(path="empty.tsv"), config=config)
2. Initialize the IndexUpdater index_updater = IndexUpdater(config=config, searcher=searcher, checkpoint=self._checkpoint)
3. Call IndexUpdater.update_searcher (or IndexUpdater.add) passing a new passage
4. Call Searcher.search querying for the newly added passage.

Result: The newly added passage does not appear in the result. Expected result: The newly added passage must appear in the search result with the highest score.

Notes:

• There is no call to persist_to_disk in the test.
• The issue does not happen when testing with a small-sized index (~112KB).

[jessiejuachon]

Issue was with the test environment: creating embeddings using an index that is different from the one that the Searcher loaded.