# 5 factors should be considered when selecting the Vector Search

Here are 5 factors that should be considered when selecting the Vector Search/Index algorithms.

### Data size:

* For data sizes under 100K, a brute-force solution utilizing a FLAT index is sufficiently efficient.
    
* Advanced algorithms may not offer significant speed improvements in such scenarios.
    

### Speed-Recall trade-off:

* When an exact match is important then brute force is the right solution
    
* Significant query latency reduction is achievable with a minor sacrifice in recall.
    

### Memory limitation:

* Some algorithms like HNSW are memory-hungry.
    
* Scalar and Product Quantization significantly reduces storage consumption, at the expense of the Recall.
    

### CPU vs GPU:

* Usually moving from CPU to GPU provides a speed boost
    
* Not all algorithms are optimized for GPU
    

### Building/Indexing time:

* Sometimes the building/indexing time is crucial.
    
* IVF has a shorter indexing time compared to HNSW.