Effective Cache Apportioning for Performance Isolation Under Compiler Guidance

Abstract

With a growing number of cores per socket in modern datacenters where multi-tenancy of a diverse set of applications must be efficiently supported, effective sharing of the last level cache is a very important problem. This is challenging because modern workloads exhibit dynamic phase behaviour -their cache requirements & sensitivity vary across different execution points. To tackle this problem, we propose Com-CAS, a compiler guided cache apportioning system that provides smart cache allocation to co-executing applications in a system. The front-end of Com-CAS is primarily a compilerframework equipped with learning mechanisms to predict cache requirements, while the backend consists of allocation framework with pro-active scheduler that apportions cache dynamically to co-executing applications. Our system improved average throughput by 21%, with a maximum of 54% while maintaining the worst individual application execution time degradation within 15% to meet SLA requirements.