This PR addresses a critical issue that was identified during benchmarking, where the recall performance unexpectedly dropped below 1. The root cause of the issue was traced to two main problems in the quantization and vector handling process:
Bit Packing of Quantized Vector: The quantized vector was not correctly updated during the bit-packing process. Instead, the same vector values were being reused, resulting in incorrect quantization of subsequent vectors.
Vector Transfer to JNI: When transferring vectors to the JNI layer, vectors were passed by reference, causing all the vectors in the VectorTransfer list to reference the same object. This led to unintended behavior where all vectors became identical, severely affecting the recall accuracy.
Testing
Performed Benchmarking with NQ Data Set Results are here s3://disk-based-ann-bq/NQ-1M-768/
Re-Call for One Bit Quantization with 2x Oversampling us 0.94
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Description
This PR addresses a critical issue that was identified during benchmarking, where the recall performance unexpectedly dropped below 1. The root cause of the issue was traced to two main problems in the quantization and vector handling process:
Testing
Performed Benchmarking with NQ Data Set Results are here s3://disk-based-ann-bq/NQ-1M-768/ Re-Call for One Bit Quantization with 2x Oversampling us 0.94
Check List
--signoff.By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license. For more information on following Developer Certificate of Origin and signing off your commits, please check here.