Hi all, I'm a bit uncertain how KNN with HNSW works in SOLR with dense vector fields and searching.
Recently I've been doing tests loading dense vectors after inferencing [images] and then checking by eye the closest matches and the results look funny (very similar images not being the nearest results as I'd normally expect). I'm unclear about HNSW in general (like what are the best policies, or a good guide or starting point, for choosing hnswMaxConnections and hnswBeamWidth values if you know the dense vector length (512) and you know you have 2 million+ documents). But one thing I'm wondering right now is with a dataset over time, where documents have been added and documents have been removed over time, can this affect the KNN search (i.e. is it better if all documents, or at least the dense vector field, had be indexed fresh) ? BTW I haven't yet moved from SOLR 9.0 to 9.1 but I do read that the HNSW codec has changed in some way so a reindex is required - I should probably try 9.1 (I would prioritise this if anyone says 9.1 is better quality or better performance for KNN searches!). Thanks for any info! Derek -- Derek Conniffe Harvey Software Systems Ltd T/A HSSL Telephone (IRL): 086 856 3823 Telephone (US): (650) 449 6044 Skype: dconnrt Email: de...@hssl.ie *Disclaimer:* This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please delete it (if you are not the intended recipient you are notified that disclosing, copying, distributing or taking any action in reliance on the contents of this information is strictly prohibited). *Warning*: Although HSSL have taken reasonable precautions to ensure no viruses are present in this email, HSSL cannot accept responsibility for any loss or damage arising from the use of this email or attachments. P For the Environment, please only print this email if necessary.