The Kernel Mode Research And Hardware Implementation Of Open VSwitch

In recent years, with the development of datacenter technology in cloud computing, virtualization technology has been widely used, more and more companies or organizations deploy their applications or services in virtual machines of datacenter, and they use virtual machines as a unit to manage and provide services. There are some merits of virtualization technology, like consolidate servers, improve server utilization, and improve business continuity and resiliency. However, the virtualization technology also brings some new challenges for datacenter, such as how to solve the problem of communication between the datacenter network edge virtual machines.In order to solve the problems of communication between edge virtual machines in datacenter network, the industry propose the VEB mechanism. VEB mechanism view to solve the communication problem of virtual machines with virtual switch which deployed in edge physical servers.Inside the servers of datacenter, a VEB realized by software is called vSwitch, Open vSwitch is a typical representative of vSwitch. vSwitch generally work in VMM layer of system, and has a good performance for packet forwarding, vSwitch can finish the communication between local virtual machines inside local physical server. However, vSwitch also has some shortcomings, the performance of vSwitch is constrained by CPU and memory bandwidth, the performance of vSwitch will bad when fewer system resources available. When there are enough system resources, vSwitch will take up a lot of resources when a lot of traffic between virtual machines need to be processed, this will affect the resources allocation flexibility of host machine.With the traffic increase of the datacenter business, the communication traffic of virtual machine is growing, the shortcomings of vSwitch cause it is difficult to meet the requirements of datacenter, and excessive consumption system resources is unbearable for host machine.This paper choose Open vSwitch as a research object of vSwitch, through the research of user mode and kernel mode of Open vSwitch, we found that kernel mode of Open vSwitch is a key part of packet processing, it affect the packet processing performance of Open vSwitch, when there are a large number of packets need to be processed, the working mechanism of kernel mode will consume a lot of resources. Through the analysis of Open vSwitch, this paper propose a solution which using hardware to realize the kernel mode function of Open vSwitch, use hardware to accelerate the process of packets, where the hardware we selected NetFPGA. This paper use NetFPGA to realize the key function of Open vSwitch kernel mode replace the same part function of Open vSwitch, and combine the remaining function of Open vSwitch with NetFPGA, NetFPGA can accelerate the speed of packet processing to improve the performance of Open vSwitch. Finally, we make a contrast of our proposal and Open vSwitch, through the throughput and resource consumption to verify the performance of our proposal is better than Open vSwitch.