Picking the right similarity_space_type name to create an inner product index

[brandenchan]

Hi ,

I am trying to create an ANN index that uses inner product as the similarity function. As far as I can see, the support for this has been implemented (#144). However, I have not found a value for knn.space_type that is accepted. The documentation here doesn't seem to list inner product.

For whatever value of knn.space_type I give, I am constantly getting

RequestError(400, 'invalid_parameter_exception', 'Unsupported space type: inner_product')

Any help would be greatly appreciated!

[jmazanec15]

Hi @brandenchan

Inner product is not available in ODFE 1.13, which was our last ODFE release: https://github.com/opendistro-for-elasticsearch/k-NN/blob/opendistro-1.13/src/main/java/com/amazon/opendistroforelasticsearch/knn/index/SpaceTypes.java. We added it to main branch after ODFE 1.13, but then with the OpenSearch fork, it was decided there would be no more ODFE releases.

It is available in OpenSearch rc1 and will be available in OpenSearch GA. Sorry for the confusion.

[brandenchan]

Great thanks!