net
A simple C++ feedforward deep nerual network forward/inference library
NET
A simple C++ feedforward deep nerual network forward/inference library. Both float and 8bits quantize model are supported in inference. Openblas is used for float GEMM(General Matrix Multiplication), and gemmlowp is used for low precision/quantize GEMM.
Tools
- tools/net-quantization: quantize float model to 8bits quantization model.
- tools/convert_keras_model.py: convert keras model to net model.
- tools/convert_kaldi_nnet1_model.py: convert kaldi nnet1 txt model to net model.
Examples
Here is an example nn-vad, which use net as inference framework for vad task.
Quantization
Experiment on Mnist, test on mnist all dev dataset(10000 images)
Precision
| Model | Size | Acurracy | Regression |
|---|---|---|---|
| origin keras model test on keras | 5.2M | 0.9825 | - |
| net float model | 2.6M | 0.9825 | 0 |
| Net 8bits model(only w_ is quantized) | 658K | 0.9823 | 0.02035% |
| Net 8bits model(w_ and bias all quantized) | 655K | 0.9824 | 0.10178% |
Time
Float model use openBlas as GEMM, and 8bits model use gemmlowp as GEMM.
Environment: 14.04.1-Ubuntu x86_64 GNU/Linux, 24core, 1.2GHZ.
| BatchSize/Time(s) | Float Model(2.6M) | 8bits Quantize Model(256K) |
|---|---|---|
| 16 | 1.802 | 3.055 |
| 32 | 1.613 | 2.409 |
| 64 | 1.218 | 2.100 |
Environment: EMUI OS, Kirin 920, 2.5GHz, 8 cores, 3G RAM.
| BatchSize/Time(ms) | Float Model(2.6M) | 8bits Quantize Model(256K) |
|---|---|---|
| 16 | 6101 | 4284 |
| 32 | 4476 | 3788 |
| 64 | 3826 | 3551 |
| 128 | 3671 | 3407 |
| 256 | 2473 | 3387 |
Addational Test
Naive vs OpenBlas GEMM
Environment: 14.04.1-Ubuntu x86_64 GNU/Linux, 24core, 1.2GHZ, Memory All matrix sampled from normal distribution, nave calculate 10 times, openblas 100times.
| Size | naive | openblas | R |
|---|---|---|---|
| 128 | 0.0435292 | 0.000142205 | 306.101 |
| 256 | 0.345951 | 0.000384407 | 899.960 |
| 512 | 3.08562 | 0.00190383 | 1620.743 |
| 1024 | 24.5289 | 0.0171441 | 1430.748 |
Row/Col major GEMM(OpenBlas)
| Size/major | Row time | Col time | R |
|---|---|---|---|
| 256 | 0.000424027 | 0.000322676 | 1.3140 |
| 512 | 0.00222023 | 0.00188339 | 1.1788 |
| 1024 | 0.0258088 | 0.0196058 | 1.3163 |