Faster Private Inference with TruncFormer
TruncFormer speeds up private inference for large language models while keeping data safe.
Patrick Yubeaton, Jianqiao Cambridge Mo, Karthik Garimella, Nandan Kumar Jha, Brandon Reagen, Chinmay Hegde, Siddharth Garg
― 6 min read
Table of Contents
In the world of big data and artificial intelligence, keeping your information safe is a hot topic. This is especially true when it comes to Large Language Models (LLMs) like ChatGPT. These models work wonders, but they often need your data, which can be quite personal. So, a clever solution called Private Inference (PI) has emerged to protect user data while still allowing these models to work their magic.
What is Private Inference?
Private inference is like having your cake and eating it too. It allows you to use powerful machine learning models without revealing your secret ingredients - in other words, your sensitive data. It uses cryptographic methods to ensure that neither you nor the model providers can see each other's data while still getting results.
However, there’s a catch. The current methods for private inference can be as slow as molasses in winter. That's because working with complex models like LLMs often involves operations that take a long time to perform. Think of it like trying to dig a hole with a spoon instead of a shovel.
Nonlinear Functions
The Problem withAt the heart of the slowdown are nonlinear functions that these models rely on. These functions are necessary for the model to understand and produce human-like responses. Unfortunately, they can be quite demanding in terms of computational resources. The usual way to handle this is through cryptographic techniques, but they add even more time to the process.
Existing approaches mostly focus on improving specific functions, like Softmax or GeLU, by using quick tricks or approximations. Each time a new fancy function comes around, researchers find themselves in a race to keep up, trying to make the latest function run faster without losing quality.
Enter TruncFormer: A Simpler Solution
Just when you thought things couldn’t get any slower, the TruncFormer model comes to the rescue. Think of TruncFormer as a superhero that swoops in to save the day. This framework allows any LLM to perform private inference more quickly by simply breaking things down into simpler parts - additions, multiplications, and some smart truncating.
TruncFormer capitalizes on the fact that nonlinear functions are actually differentiable. That means they can be approximated with basic arithmetic and smart truncation techniques. By separating complex operations into manageable bits, TruncFormer saves time and effort.
The Importance of Truncation
Why is truncation so important, you ask? Well, in the world of private inference, truncation helps manage the size of the numbers being processed. If numbers get too big, they can cause all sorts of problems in a fixed-size field (think of it as a limited-size box for your data). So, knowing precisely where to truncate can prevent overflow and significant computational delays.
Previous methods typically made truncation after every operation. That’s like putting a speed bump every few feet on a long road trip. With TruncFormer, we can trim the fat and only add those bumps where necessary, making the journey smoother.
The Road to Faster Inference
With TruncFormer, private inference is no longer an endurance test. The framework is built on two main ideas:
- Nonlinearities can be approximated through simpler functions, which means they can be computed with basic operations that are much faster.
- Instead of blindly truncating after every complex operation, this model intelligently decides when truncation should take place based on the potential for overflow.
Combining these insights allows TruncFormer to speed up the inference process while maintaining the quality of the results.
A Peek Under the Hood
So how does this magic happen? TruncFormer begins its work by transforming weights and hidden states from a floating-point representation (which is difficult for cryptographic protocols to work with) into a fixed-point representation. This makes everything compatible with cryptographic operations and efficient to process.
Now, the beauty of the system lies in its ability to analyze the sequence of operations and determine where Truncations are necessary. Think of it like a chef taking the time to pick the right ingredients before cooking their signature dish - a little focus can save a lot of time!
How Do the Numbers Stack Up?
To assess how well TruncFormer works, researchers ran tests comparing it with existing methods on popular LLMs like Llama-7B and Gemma-2B. The results were encouraging. The new method delivered comparable accuracy while significantly reducing Latency (or the time it takes to get results).
Whether it was coding challenges or math problems, TruncFormer kept pace with its competitors. In some instances, it even performed faster! Imagine getting your food order faster than expected at a restaurant. It’s like hitting the jackpot!
Is This for Everyone?
You might be wondering if this cool technology is accessible for the average Joe. While TruncFormer is a step in the right direction, private inference is still not as fast as one might hope. We’re still talking about potentially hours for a single inference. For now, it’s best suited for tasks where privacy is crucial, such as healthcare data, banking, or any situation where sensitive information is at stake.
Future Directions
So, where does the future lead us? As researchers work to refine and enhance private inference, a key takeaway is that truncation is a critical operation. Focusing on optimizing this aspect could lead to even more significant latency reductions.
We may be on the brink of finding new ways to make private inference practical. The aim is to keep up with the rapid advancements in AI without compromising efficiency or security.
Summing It Up
In a nutshell, the TruncFormer framework offers a smart, efficient way to handle private inference with large language models. It promises to make the process faster while ensuring that sensitive data remains secure.
For now, it’s not quite the silver bullet we all want - but it’s certainly a step in the right direction. As technology evolves, we hope to see even better systems that can make private inference as easy as ordering a pizza (without sharing your toppings with anyone!).
In conclusion, while private inference may still have a way to go, with innovations like TruncFormer, we can look forward to a future where our data remains ours alone - and where waiting for answers isn't quite as painful. Who knows? Perhaps one day, it will be fast enough to make a coffee break feel like an eternity!
Title: TruncFormer: Private LLM Inference Using Only Truncations
Abstract: Private inference (PI) serves an important role in guaranteeing the privacy of user data when interfacing with proprietary machine learning models such as LLMs. However, PI remains practically intractable due to the massive latency costs associated with nonlinear functions present in LLMs. Existing works have focused on improving latency of specific LLM nonlinearities (such as the Softmax, or the GeLU) via approximations. However, new types of nonlinearities are regularly introduced with new LLM architectures, and this has led to a constant game of catch-up where PI researchers attempt to optimize the newest nonlinear function. We introduce TruncFormer, a framework for taking any LLM and transforming it into a plaintext emulation of PI. Our framework leverages the fact that nonlinearities in LLMs are differentiable and can be accurately approximated with a sequence of additions, multiplications, and truncations. Further, we decouple the add/multiply and truncation operations, and statically determine where truncations should be inserted based on a given field size and input representation size. This leads to latency improvements over existing cryptographic protocols that enforce truncation after every multiplication operation. We open source our code for community use.
Authors: Patrick Yubeaton, Jianqiao Cambridge Mo, Karthik Garimella, Nandan Kumar Jha, Brandon Reagen, Chinmay Hegde, Siddharth Garg
Last Update: Dec 1, 2024
Language: English
Source URL: https://arxiv.org/abs/2412.01042
Source PDF: https://arxiv.org/pdf/2412.01042
Licence: https://creativecommons.org/licenses/by/4.0/
Changes: This summary was created with assistance from AI and may have inaccuracies. For accurate information, please refer to the original source documents linked here.
Thank you to arxiv for use of its open access interoperability.