ElaX: Provisioning Resource Elastically for Containerized Online Cloud Services
Yanan Yang, Laiping Zhao, Zhigang Li, Lihai Nie, Peiqi Chen, Keqiu Li · 2019
To reduce the cost of online cloud services, service providers often employ the elastic approach that allows tenants to "scale out" or "scale up" their applications at runtime. However, the traditional virtual machine-based approach cannot meet the fine-grained fluctuating demand due to its slow startup time and high reconfiguration cost. To address this challenge, we present ElaX, an online service manager that minimizes the resource provisioning cost for containerized online services while guaranteeing their tail latency requirement. ElaX designs a workload-aware resource allocation mechanism for containerized online services through the collaboration of three key components: First, Workload predictor is able to precisely predict the workload in periodic scenario, through a LSTM (Long Short-Term Memory) network; Second, Resource reservation allocates the just-right amount of resource supporting the predicted workload, using the combination of both scale-up and scale-out operations; Third, Online controller guarantees the tail latency requirement during prediction failures through a feedback-based control method, and further reduces the provision cost through resource reclamation. Our experiments on the two production workloads demonstrate that ElaX can reduce the average resource over-provisioning cost by more than 32.6% while guaranteeing the tail latency requirement.