Workload isolation in cloud computing is a critical practice for enhancing efficiency, security, and compliance by segregating computing tasks into distinct resources or infrastructure. This separation ensures that compromised workloads do not affect others, thereby reducing security risks, enhancing performance by preventing resource competition, and simplifying regulatory compliance. Achieving workload isolation involves various strategies, including resource governance, access control, and network-level isolation. DeltaStream, a serverless stream processing platform, exemplifies workload isolation by enabling each query to run in its dedicated environment using Apache Flink, offering multiple deployment options like dedicated and private SaaS deployments, and employing role-based access control to manage data access. These features ensure secure, performant computational queries while providing assurance that data remains confined within non-shared networks, crucial for maintaining security and compliance in cloud products.