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arXiv · 2412.08938

Mercury: QoS-Aware Tiered Memory System

Jiaheng Lu·Yiwen Zhang·Hasan Al Maruf·Minseo Park·Yunxuan Tang·Fan Lai·Mosharaf Chowdhury
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Abstract

Memory tiering has received wide adoption in recent years as an effective solution to address the increasing memory demands of memory-intensive workloads. However, existing tiered memory systems often fail to meet service-level objectives (SLOs) when multiple applications share the system because they lack Quality-of-Service (QoS) support. Consequently, applications suffer severe performance drops due to local memory contention and memory bandwidth interference. In this paper, we present Mercury, a QoS-aware tiered memory system that ensures predictable performance for coexisting memory-intensive applications with different SLOs. Mercury enables per-tier page reclamation for application-level resource management and uses a proactive admission control algorithm to satisfy SLOs via per-tier memory capacity allocation and intra- and inter-tier bandwidth interference mitigation. It reacts to dynamic requirement changes via real-time adaptation. Extensive evaluations show that Mercury improves application performance by up to 53.4% and 20.3% compared to TPP and Colloid, respectively.

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Jiaheng Lu, Yiwen Zhang, Hasan Al Maruf, Minseo Park, Yunxuan Tang, Fan Lai, Mosharaf Chowdhury. 2024-12-12. Mercury: QoS-Aware Tiered Memory System. https://arxiv.org/abs/2412.08938

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