Tianrui Hu

Nihal Sanjay Singh, Keito Kobayashi, Qixuan Cao et al.

Extending Moore's law by augmenting complementary-metal-oxide semiconductor (CMOS) transistors with emerging nanotechnologies (X) has become increasingly important. One important class of problems involve sampling-based Monte Carlo algorithms used in probabilistic machine learning, optimization, and quantum simulation. Here, we combine stochastic magnetic tunnel junction (sMTJ)-based probabilistic bits (p-bits) with Field Programmable Gate Arrays (FPGA) to create an energy-efficient CMOS + X (X = sMTJ) prototype. This setup shows how asynchronously driven CMOS circuits controlled by sMTJs can perform probabilistic inference and learning by leveraging the algorithmic update-order-invariance of Gibbs sampling. We show how the stochasticity of sMTJs can augment low-quality random number generators (RNG). Detailed transistor-level comparisons reveal that sMTJ-based p-bits can replace up to 10,000 CMOS transistors while dissipating two orders of magnitude less energy. Integrated versions of our approach can advance probabilistic computing involving deep Boltzmann machines and other energy-based learning algorithms with extremely high throughput and energy efficiency.

Tianrui Hu, Dimitrios Liakopoulos, Xiwen Wei et al.

With the rise of social media, misinformation has become increasingly prevalent, fueled largely by the spread of rumors. This study explores the use of Large Language Model (LLM) agents within a novel framework to simulate and analyze the dynamics of rumor propagation across social networks. To this end, we design a variety of LLM-based agent types and construct four distinct network structures to conduct these simulations. Our framework assesses the effectiveness of different network constructions and agent behaviors in influencing the spread of rumors. Our results demonstrate that the framework can simulate rumor spreading across more than one hundred agents in various networks with thousands of edges. The evaluations indicate that network structure, personas, and spreading schemes can significantly influence rumor dissemination, ranging from no spread to affecting 83\% of agents in iterations, thereby offering a realistic simulation of rumor spread in social networks.

Dimitrios Liakopoulos, Tianrui Hu, Prasoon Sinha et al.

Large Language Models (LLMs) are becoming ubiquitous across industries, where applications demand they fulfill diverse user intents. However, developers currently face the challenge of manually exploring numerous deployment configurations - combinations of parallelism and compression techniques that impact resource usage, latency, cost, and accuracy - to meet these intents. Assessing the impact of these configurations on user metrics requires extensive, costly profiling for each model. Existing approaches avoid this expense by using fixed, static configurations, but this often leads to sub-optimal performance and higher costs. Moreover, none of these solutions dynamically adapt to changing user intents to balance latency and cost, effectively. We present iServe, an automated, intent-based system for distributed LLM inference. Instead of manually selecting deployment configurations, developers simply specify their intent - such as minimizing latency, reducing cost, or meeting specific targets for either. iServe introduces fingerprints, lightweight representations of LLMs, to efficiently estimate how different configurations impact latency and memory usage. Based on these insights and GPU availability, iServe dynamically selects the optimal configuration to align with the user's intent. For various LLMs and query arrival rates, iServe best meets user intents compared to state-of-the-art systems by reducing latency by 77.62% and SLO violations by 7.09x while improving GPU throughput by 4.72x. Moreover, iServe's fingerprint-based profiling reduces profiling cost by 6.05x (GPU-hours) compared to baselines.