Introduction

NFL is a two-stage learned index framework, consisting of a normalizing flow that performs a Distribution Transformation on the key distribution and a learned index that achieves excellent performance on the near-uniform key distritbuion with small buffers.

Early access: https://arxiv.org/abs/2205.11807

Requirements

• Intel MKL 11.3
• CMake 3.12
• GNU C++ 17
• OpenMP

Getting Started

Acitivating intel mkl.

$ source ~/intel/oneapi/setvars.sh --force intel64

Downloading libraries and compiling codes.

$ bash scripts/bootstrap.sh

Generating workloads and configs.

$ bash scripts/generate_workloads.sh
$ bash scripts/generate_configs.sh

Reproducing results.

$ bash scripts/benchmark.sh

Clearing.

$ bash scripts/clear.sh

Training

To train our numerical flowl, please follow the guideline in the train directory.

First, run the script to generate training data for the flow.

$ bash scripts/prepare_keys_for_flows.sh

Then, run the script in the train directory.

$ bash train/train_flow.sh

Results

The results are shown in the following format.

(dataset name) (index name) (batch size) (bulk loading time) (transformation time in bulk loading) (model size) (index size) (overall throughput) (avg-T) (avg-I) (50-T) (50-I) (75-T) (75-I) (99-T) (99-I) (995-T) (995-I) (9999-T) (9999-I) (max-T) (max-I)

where 'T' represents the transformation time, 'I' represents the indexing latency.

Contact

Please be free to contact us via shangyuwu2-c@my.cityu.edu.hk.