Abstract: Response time is an important performance indicator of the service level objective (SLO),which is related to the usage of resources.If resources are sufficient to ensure the normal execution of the request,the response time is short.If resources are insufficient,the request needs to wait for resources,and the response time is long.In the cloud computing virtualization environment,the control of resource access includes both the control of the overall resource and the control of individual resources such as CPU and network bandwidth.However,there are currently few direct control of network I/O requests to ensure response time.In order to achieve better performance,virtualization technology mostly uses the para-virtualization framework Virtio.Network I/O requests are transmitted through the Virtio shared channel,making it possible to set up a gating mechanism for network I/O requests in Virtio.Therefore,the study uses the two-end aggregation method (TAM) to propose gating mechanism for real-time network I/O requests (GMRNR),which controls the time when the network I/O request passes Virtio to ensure the response time of various requests.GMRNR is set up in the virtio-net module of Virtio front-end and classifies requests according to their response time indicators.It uses timers and aggregation queue length to control the time and aggregation frequency of diffe-rent levels of requests through Virtio to ensure the response time of the request.Experimental tests show that GMRNR can distinguish the priority of network I/O requests,and when resources are sufficient,network I/O requests of different levels can be completed within their respective required time.When resources are insufficient,the response time of high-priority network I/O requests is given priority.Meanwhile,GMRNR has high resource utilization efficiency.

Key words: Gating mechanism, Network I/O requests, Priority, Response time, Service level objective(SLO), Virtio