Dynamic storage cache allocation in multi-server architectures

Abstract

We introduce a dynamic and efficient shared cache management scheme, called Maxperf, that manages the aggregate cache space in multi-server storage architectures such that the service level objectives (SLOs) of concurrently executing applications are satisfied and any spare cache capacity is proportionately allocated according to the marginal gains of the applications to maximize performance. We use a combination of Neville's algorithm and linear-programming-model to discover the required storage cache partition size, on each server, for every application accessing that server. Experimental results show that our algorithm enforces partitions to provide stronger isolation to applications, meets application level SLOs even in the presence of dynamically changing storage cache requirements, and improves I/O latency of individual applications as well as the overall I/O latency significantly compared to two alternate storage cache management schemes, and a state-of-the-art single server storage cache management scheme extended to multi-server architecture.