If ever there have been a salient instance of a counter-intuitive approach, it might be quantization of neural networks. Quantization reduces the precision of the weights and different tensors in neural community fashions, usually drastically. It’s no shock that lowering the precision of weights and different parameters from, say, 32-bit floats to 8-bit integers, makes the mannequin run sooner, and permits it to run in much less highly effective processors with far much less reminiscence. The gorgeous, counter-intuitive discovering is that quantization could be achieved whereas largely preserving the accuracy of the mannequin.
Why do we want quantization? The present giant language fashions (LLMs) are huge. The finest fashions have to run on a cluster of server-class GPUs; gone are the times the place you could possibly run a state-of-the-art mannequin regionally on one GPU and get fast outcomes. Quantization not solely makes it doable to run a LLM on a single GPU, it lets you run it on a CPU or on an edge machine.
Post-training quantization
Post-training quantization is a conversion approach that may scale back mannequin measurement whereas additionally bettering CPU and {hardware} accelerator latency, with little degradation in mannequin accuracy.
Given how mature TensorFlow Lite is in comparison with, say, the Gen AI mannequin du jour (most likely Mistral AI’s Codestral, which was launched the day I wrote this), it’s value how TensorFlow Lite implements quantization. First of all, TensorFlow Lite implements three choices for quantization:
Technique |
Benefits |
Hardware |
Dynamic vary quantization |
4x smaller, 2x to 3x speedup |
CPU |
Full integer quantization |
4x smaller, 3x+ speedup |
CPU, Edge TPU, Microcontrollers |
Float16 quantization |
2x smaller, GPU acceleration |
CPU, GPU |
In the choice tree that accompanies this desk, the TensorFlow Lite documenters define the issues for selecting a quantization approach. It’s value studying via the logic. In a nutshell, the most effective post-quantization methodology to your use case will rely in your {hardware} help for integer or floating level operations and whether or not you may present a consultant information set for calibration.
Dynamic vary quantization
Then they clarify why dynamic vary quantization is the standard start line: It offers diminished reminiscence utilization and sooner computation with out requiring you to offer a consultant information set for calibration. Dynamic vary quantization statically quantizes solely the weights from floating…