Large language models (LLMs) achieve remarkable performance across diverse tasks but face increasing GPU-memory demands due to the growing variety and complexity of downstream tasks. Efficient inference has thus become essential, especially for resource-limited settings. In this paper, we propose LoRA Decompose, a novel compression approach based on a key insight: instruction-fine-tuned models share a common pretrained-like base component and differ primarily through low-rank, LoRA-like delta components. Leveraging this observation, we reformulate the inference problem as a constrained optimization task that jointly identifies a shared low-rank structure across multiple models, significantly reducing their memory footprints. We solve this optimization efficiently using a custom-designed block coordinate descent algorithm, converging quickly within a few iterations. Empirical experiments with Llama-2 7B and 13B models demonstrate that our method achieves a remarkable >32x GPU memory reduction while preserving task accuracy, allowing substantial efficiency gains for practical deployment.

Software testing plays a crucial role in software engineering, ensuring the reliability and correctness of evolving systems. Well-maintained test suites are essential for ensuring software quality. However, in modern development cycles that emphasize rapid feature iteration, the co-evolution of test suites often lags behind, leading to more appearance of obsolete tests. To this end, automated approaches for updating obsolete test code have been proposed, and recent approaches have achieved the state-of-the-art performance with the support of large language models (LLMs). This paper presents COMMITUP, a new approach that leverages LLMs to effectively automate method-level obsolete test code updates. COMMITUP mimics how humans solve the problem, first comprehending the code modifications, searching for similar examples to imitate, and finally performing the update. We evaluate COMMITUP on a curated dataset from real-world Java projects. The results demonstrate the superior performance of COMMITUP, achieving 96.4%, 94.4%, 93.1% success rates for generating compilable, runtime failure-free, and full coverage updates, respectively. We believe our study can provide new insight into LLM-based test code update. The dataset and code are available at https://github.com/SoftWiser-group/CommitUp.