Storage System I/O Latency Control via QoS Delay

The storage system pre-calculates and stores QoS data (including delay periods) for each disk file in advance. When an I/O request arrives, the system directly retrieves the pre-determined delay period from the QoS data associated with the target disk file, rather than calculating it in real-time. This preliminary preparation enables the system to enforce I/O rate limiting and balance load across virtual machines effectively, preventing any single VM from monopolizing I/O resources and causing latency for others.

The system applies different QoS policies and delay periods to different disk files based on their specific requirements and the virtual machines they serve. Each disk file has its own QoS data with customized delay periods, allowing the storage system to locally optimize I/O handling for each file-VM-hypervisor combination. This granular, localized control ensures that multiple hypervisors can connect and share resources while maintaining fair I/O distribution and preventing latency issues.

The storage system automatically retrieves QoS data for each disk file and determines the appropriate delay period without requiring manual intervention or complex administrative configuration. The system serves itself by autonomously enforcing I/O rate limiting based on pre-stored QoS parameters, eliminating the need for administrators to manually manage volume allocations and QoS policies for each virtual machine. This self-service approach maintains reliable QoS control while significantly reducing operational complexity.