OpenSearch not using Lucene as a vector search engine

Hey I am not sure if I am missing something here but this is not an apples to apples comparison right now. In the blog it was claimed that both were using Lucene for vector storage and retrieval unless I misread it but here the code is using FAISS.

I really enjoyed the blog and am a big fan of BBQ but wanted to make sure I understood what’s being compared here.

https://github.com/elastic/competitive-benchmarking-studies/blob/e8682663230b0d70a6d3a8ceca9cbe12c91de4a7/es-9.3-vs-os-3.5-vector-search/jingra/src/benchmark/engines/opensearch.py#L50

Start with jingra/src/benchmark/engines/opensearch.py at the linked line and compare its vector storage and retrieval setup with the blog's claim that both systems use Lucene. Confirm whether the benchmark is using FAISS for OpenSearch, then document or correct the comparison so the two engines use the stated setup.

Written by the indexing model from the issue text.