μslice: Toward Accurate Sub-Core Allocation with eBPF
TL;DR
An eBPF-based scheduling framework is designed and implemented that complements existing kernel mechanisms to improve the accuracy of fine-grained CPU allocation while maintaining low overhead and demonstrates that the proposed approach significantly reduces resource overallocation and performance variability compared to conventional OS resource control mechanisms.
Abstract
The rise of cloud service models such as serverless computing and microservices has driven the adoption of fine-grained resource provisioning and billing, allowing users to request fractional CPU allocations at sub-core granularity. However, existing operating system mechanisms for CPU bandwidth control were designed for much coarser resource allocations. As a result, they can introduce substantial resource overallocation and performance variability when enforcing the small CPU shares required by modern cloud workloads. In this paper, we investigate whether eBPF can bridge this gap by enabling more precise and responsive CPU bandwidth enforcement. We design and implement an eBPF-based scheduling framework, μslice, that complements existing kernel mechanisms to improve the accuracy of fine-grained CPU allocation while maintaining low overhead. Our evaluation demonstrates that the proposed approach significantly reduces resource overallocation and performance variability compared to conventional OS resource control mechanisms.