Function Description

AscendIndexFlatL2 is a feature brute force search algorithm that stores FP16 floating point numbers and uses L2 distance.

Multi-thread concurrent calling is supported. You need to set the environment variable MX_INDEX_MULTITHREAD to 1, that is, export MX_INDEX_MULTITHREAD=1. If this variable is set to another value or is not set, the multi-thread function is disabled. Currently, FeatureRetrieval uses the OMP for performance acceleration. The OMP cannot be used together with other multi-thread mechanisms. If new threads are repeatedly created to use the OMP, the memory usage keeps increasing. Therefore, you are advised to use fixed threads to run retrieval tasks.

The AscendIndexFlatL2 algorithm support online operator conversion. If the environment variable MX_INDEX_USE_ONLINEOP is set to 1 (that is, export MX_INDEX_USE_ONLINEOP=1), operators are converted and called online. To use online operators, you need to call (void)aclFinalize() explicitly at the end of the application. The header file must be included, for example, #include "acl/acl.h".