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arXiv · 2510.07449

How long can you sleep? Idle Time System Inefficiencies and Opportunities

Georgia Antoniou·Haris Volos·Jawad Haj Yahya·Yiannakis Sazeides
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Abstract

This work introduces a model-based framework that reveals the idle opportunity of modern servers running latency-critical applications. Specifically, three queuing models, M/M/1, cxM/M/1, and M/M/c, are used to estimate the theoretical idle time distribution at the CPU core and system (package) level. A comparison of the actual idleness of a real server and that from the theoretical models reveals significant missed opportunities to enter deep idle states. This inefficiency is attributed to the idle-governor inaccuracy and the high latency to transition to/from legacy deep-idle states. The proposed methodology offers the means for an early-stage design exploration and insights into idle time behavior and opportunities for varying server system configurations and load.

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Georgia Antoniou, Haris Volos, Jawad Haj Yahya, Yiannakis Sazeides. 2025-10-08. How long can you sleep? Idle Time System Inefficiencies and Opportunities. https://arxiv.org/abs/2510.07449

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