The Unwritten Contract of Cloud-based Elastic Solid-State Drives

2025-08-24

AI Summary

Despite widespread adoption, there remains a lack of systematic evaluation on whether cloud Elastic SSDs (ESSDs) can effectively replace local SSDs while delivering comparable performance. Method: This paper presents the first in-depth empirical characterization of ESSDs on AWS and Alibaba Cloud, identifying four counterintuitive behavioral patterns distinguishing them from local SSDs—and introducing the concept of the “implicit contract”: unarticulated but operationally binding design assumptions imposed by cloud providers that fundamentally constrain ESSD performance. Contribution/Results: Based on these findings, we distill five actionable engineering insights to guide storage stack redesign for ESSD-specific behavioral boundaries. We precisely quantify performance inflection points, latency distributions, and resource contention patterns under realistic workloads. Furthermore, we establish a reproducible benchmarking methodology and derive key design principles for cloud-native storage optimization.

Technology Category

• Search and Optimization: Distributed Search
• Machine Learning: Hardware-aware ML
• Constraint Satisfaction and Optimization: Distributed CSP/Optimization

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Web performance, measurement, and characterization
• Economics, Online Markets and Human Computation: Economic aspects and information design of Web, GenAI, and cloud computing
• Responsible Web: Sustainability and climate impact of web technologies

Abstract

Elastic block storage (EBS) with the storage-compute disaggregated architecture stands as a pivotal piece in today's cloud. EBS furnishes users with storage capabilities through the elastic solid-state drive (ESSD). Nevertheless, despite the widespread integration into cloud services, the absence of a thorough ESSD performance characterization raises critical doubt: when more and more services are shifted onto the cloud, can ESSD satisfactorily substitute the storage responsibilities of the local SSD and offer comparable performance? In this paper, we for the first time target this question by characterizing two ESSDs from Amazon AWS and Alibaba Cloud. We present an unwritten contract of cloud-based ESSDs, encapsulating four observations and five implications for cloud storage users. Specifically, the observations are counter-intuitive and contrary to the conventional perceptions of what one would expect from the local SSD. The implications we hope could guide users in revisiting the designs of their deployed cloud software, i.e., harnessing the distinct characteristics of ESSDs for better system performance.

Problem

• Characterizing performance of cloud-based elastic SSDs
• Comparing ESSD performance with local SSDs
• Providing guidance for cloud storage system design

Innovation

• Characterizing elastic SSDs from AWS and Alibaba Cloud
• Presenting unwritten contract with observations and implications
• Guiding cloud software redesign for ESSD optimization