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Serverless computing has gained traction due to its event-driven architecture and “pay for use” (PFU) billing model. However, our analysis reveals that current billing practices do not align with true resource consumption. This paper challenges the prevailing SLIM (static, linear, interactive-only model) assumptions that underpin existing billing models, demonstrating that current billing does not realize PFU for realistic workloads. We introduce the Nearly Pay-for-Use (NPFU) billing model, which accommodates varying CPU and memory demands, spot cores, and preemptible memory. We also introduce Leopard, an NPFU-based serverless platform that integrates billing awareness into several major subsystems: CPU scheduler, OOM killer, admission controller, and cluster scheduler. Experimental results indicate that Leopard benefits both providers and users, increasing throughput by more than 2x and enabling cost reductions. 

We present Cloudscape, a dataset of nearly 400 cloud archi- tectures deployed on AWS. We perform an in-depth analysis of the usage of storage services in cloud systems. Our findings include: S3 is the most prevalent storage service (68%), while file system services are rare (4%); heterogeneity is common in the storage layer; storage services primarily interface with Lambda and EC2, while also serving as the foundation for more specialized ML and analytics services. Our findings provide a concrete understanding of how storage services are deployed in real-world cloud architectures, and our analysis of the popularity of different services grounds existing research. 

Caches are pervasively used in content delivery networks (CDNs) to serve requests close to users and thus reduce content access latency. However, designing latency-optimal caches are challenging in the presence of delayed hits, which occur in high-throughput systems when multiple requests for the same content occur before the content is fetched from the remote server. In this paper, we propose a novel timer-based mechanism that provably optimizes the mean caching latency, providing a theoretical basis for the understanding and design of latency-aware (LA) caching that is fundamental to content delivery in latency-sensitive systems. Our timer-based model is able to derive a simple ranking function which quickly informs us the priority of a content for our goal to minimize latency. Based on that we propose a lightweight latency-aware caching algorithm named LA-Cache. We have implemented a prototype within Apache Traffic Server, a popular CDN server. The latency achieved by our implementations agrees closely with theoretical predictions of our model. Our experimental results using production traces show that LA-Cache consistently reduces latencies by 5%-15% compared to state-of-the-art methods depending on the backend RTTs.