MilvusException: <MilvusException: (code=65535, message=efConstruction out of range: [1, 2147483647])>

Question

I have the following error: MilvusException: <MilvusException: (code=65535, message=efConstruction out of range: [1, 2147483647])>

while I am creating HNSW indexing on milvus db. any suggestion would be great. nothing on the internet.

My vector size is 30552. maybe that can be the problem. I am not sure. just looking for a logical explanation.

UPDATE-1: I have updated my create index parameters for efconstruction parameter. here is the configuration: {'metric_type': 'ss', 'index_type': 'bb', 'params': {'nlist': 5, 'efConstruction': 40}}

after that I am getting the following error:

MilvusException: <MilvusException: (code=65535, message=M out of range: [1, 2048])>

Answer 1

delete existing vector DB. Start a fresh.

mostly the previous indexes created cause a conflict

Answer 2

• 'nlist' is a hyperparameter of IVF_flat index.
• 'M', 'efConstruction', 'ef' are hyperparameters for HNSW index.

HNSW best practice params. Start with M: 4~64, larger M for larger data and larger embedding lengths. Then ef = efConstruction = M * 2.

References:

• Milvus docs: https://milvus.io/docs/index.md
• HNSW docs: https://github.com/nmslib/hnswlib/blob/master/ALGO_PARAMS.md

Answer 3

After adding efconstruction and M parameters to my creat_index code. Problem is solved for me.

here is the my latest index parameter: {'metric_type': 'IP', 'index_type': 'HNSW', 'params': {'nlist': 1024, 'efConstruction': 40, 'M': 1024}}

Note: you may not need nlist parameter. just ignore that one.