User Disengagement-Oriented Target Enforcement for Multi-Tenant Database Systems

Unexpected long query latency of a database system can cause domino effects on all the upstream services and severely degrade end users' experience with unpredicted long waits, resulting in an increasing number of users disengaged with the services and thus leading to a high user disengagement ratio (UDR). A high UDR usually translates to reduced revenue for service providers. This paper proposes UTSLO, a UDR-oriented SLO guaranteed system, which enables a database system to support multi-tenant UDR targets in a cost-effective fashion through UDR-oriented capacity planning and dynamic UDR target enforcement. The former aims to estimate the feasibility of UDR targets while the latter dynamically tracks and regulates per-connection query latency distribution needed for accurate UDR target guarantee. In UTSLO, the database service capacity can be fully exploited to efficiently accommodate tenants while minimizing resources required for UDR target guarantee.