One of the challenges of deploying multitenant cloud-hosted services that are designed to use (or be integrated with) several components is how to implement the required degree of isolation between the components when there is a change in the workload. Achieving the highest degree of isolation implies deploying a component exclusively for one tenant; which leads to high resource consumption and running cost per component. A low degree of isolation allows sharing of resources which could possibly reduce cost, but with known limitations of performance and security interference. This paper presents a model-based algorithm together with four variants of a metaheuristic that can be used with it, to provide near-optimal solutions for deploying components of a cloud-hosted application in a way that guarantees multitenancy isolation. When the workload changes, the model-based algorithm solves an open multiclass QN model to determine the average number of requests that can access the components and then uses a metaheuristic to provide near-optimal solutions for deploying the components. Performance evaluation showed that the obtained solutions had low variability and percent deviation when compared to the reference/optimal solution. We also provide recommendations and best practice guidelines for deploying components in a way that guarantees the required degree of isolation.

中文翻译：

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优化部署云托管应用程序的组件，以确保多租户隔离

部署旨在使用（或与多个组件集成）多租户云托管服务的挑战之一是，当工作负载发生变化时，如何在组件之间实现所需的隔离度。实现最高程度的隔离意味着专门为一个租户部署一个组件；这会导致高资源消耗和每个组件的运行成本。较低的隔离度允许共享资源，这可能会降低成本，但存在性能和安全干扰的已知限制。本文提出了一种基于模型的算法以及可与之一起使用的元启发式算法的四个变体，以提供一种确保多租户隔离的方式来为部署云托管应用程序的组件提供近乎最佳的解决方案。当工作负载发生变化时，基于模型的算法将解决开放的多类QN模型，以确定可以访问组件的平均请求数量，然后使用元启发式方法为部署组件提供近乎最佳的解决方案。性能评估表明，与参考溶液/最佳溶液相比，所得溶液具有较低的变异性和百分比偏差。我们还提供建议和最佳实践准则，以确保所需隔离度的方式部署组件。性能评估表明，与参考溶液/最佳溶液相比，所得溶液具有较低的变异性和偏差百分比。我们还提供建议和最佳实践准则，以确保所需隔离度的方式部署组件。性能评估表明，与参考溶液/最佳溶液相比，所得溶液具有较低的变异性和偏差百分比。我们还提供建议和最佳实践准则，以确保所需隔离度的方式部署组件。