README.md

Revisiting the Inverted Indices for Billion-Scale Approximate Nearest Neighbors

This is the code for the current state-of-the-art billion-scale nearest neighbor search system presented in the paper:

Revisiting the Inverted Indices for Billion-Scale Approximate Nearest Neighbors,
Dmitry Baranchuk, Artem Babenko, Yury Malkov

The code is developed upon the FAISS library.

Build

Today we provide the C++ implementation supporting only the CPU version, which requires a BLAS library.

The code requires a C++ compiler that understands:

• the Intel intrinsics for SSE instructions
• the GCC intrinsic for the popcount instruction
• basic OpenMP

Installation instructions

1. Clone repository

git clone https://github.com/dbaranchuk/ivf-hnsw --recursive

2. Configure FAISS

There are a few models for makefile.inc in the faiss/example_makefiles/ subdirectory. Copy the relevant one for your system to faiss/ and adjust to your needs. In particular, for ivf-hnsw project, you need to set a proper BLAS library paths. There are also indications for specific configurations in the troubleshooting section of the FAISS wiki

3. Replace FAISS CMakeList.txt

Replace faiss/CMakeList.txt with CMakeList.txt.faiss in order to deactivate building of unnecessary tests and the GPU version.

mv CMakeLists.txt.faiss faiss/CMakeLists.txt

4. Build project

cmake . && make

Data

The proposed methods are tested on two 1 billion datasets: SIFT1B and DEEP1B. For using provided examples, all data files have to be in data/SIFT1B and data/DEEP1B.

Data files:

• SIFT1B:

  • dataset, Datasets for approximate nearest neighbor search

  cd data/SIFT1B && bash load_sift1b.sh

  • learned 993127 centroids, GoogleDrive
  • precomputed indices of assigned base points, GoogleDrive

• DEEP1B:

  • dataset, YandexDrive

  cd data/DEEP1B && python load_deep1b.py

  • learned 999973 centroids, GoogleDrive
  • precomputed indices of assigned base points, GoogleDrive

Note: precomputed indices are optional, as it just lets avoid assigning step, which takes about 2-3 days for 2^20 centroids.

Run

tests/ provides two tests for each dataset:

• IVFADC
• IVFADC + Grouping (+ Pruning)

Each test requires many options, so we provide bash scripts in examples/, exploiting these tests. Scripts are commented and the Parser class provides short descriptions for each option.

Make sure that:

• models/SIFT1B/ and models/DEEP1B/ exist

mkdir models && mkdir models/SIFT1B && mkdir models/DEEP1B

• the data is placed to data/SIFT1B/ and data/DEEP1B/ respectively (or just make symbolic links)
• run, for example:

bash examples/run_deep1b_grouping.sh

Documentation

The doxygen documentation gives per-class information