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OPTIMIZING ATTENTION AND INFERENCE IN LARGE LANGUAGE MODELS: BALANCING EFFICIENCY, INTERPRETABILITY, AND ENERGY CONSUMPTION

Abstract

The rapid growth of large language models (LLMs) has intensified interest in the computational, energetic, and interpretive properties of attention mechanisms and supporting inference infrastructure. This article synthesizes theoretical and empirical insights across two intertwined research streams: the internal mechanics of attention in transformer models (comprehending the functional role and interpretability of multi-head and sparse attention) and systems-level approaches to efficient, low-latency, and energy-aware inference (including KV caches, heavy-hitter techniques, and firmware-level scheduling). We present a cohesive conceptual framework that reconciles apparent tensions—such as whether attention weights constitute explanations of model behavior and whether dense multi-head attention is uniformly necessary—by connecting representational redundancy to opportunities for structured sparsity and cache-aware inference. Building on prior analyses of attention distribution, heavy-hitter phenomena in token streams, and lifecycle energy accounting, we argue for an integrative approach: adaptive attention architectures that dynamically reallocate head resources, combined with inference-time KV cache management and scheduling policies that prioritize heavy-hitter contexts. We discuss methodological principles for evaluating such architectures—focusing on causal probing, ablation procedures, and realistic inference benchmarks that capture latency, throughput, and energy budgets. Limitations of extant studies are detailed, and we outline a roadmap for research blending model-centric and systems-centric innovation. Our synthesis highlights how careful co-design of attention mechanisms and inference systems can preserve or even enhance model fidelity while substantially reducing computational and environmental cost, offering concrete directions for both algorithmic research and practical deployment.

Keywords

Attention interpretability, sparse attention, heavy-hitter

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References

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