Research On Performance Optimization And Security Enhancement Techniques For RDMA Based On SoftRoCE

As the scale of cloud computing expands,the transmission rate requirements for data center networks continue to increase.Infiniband has proposed RDMA technology to meet the demand for low latency and high bandwidth in data center networks.RDMA technology has been widely used in network-intensive scenarios such as high-performance computing,big data analytics,and distributed storage.Although the performance of RDMA technology is impressive,its deployment cost is expensive.In order to be compatible with devices that have not yet deployed RDMA network interface cards,IBTA proposed Soft Ro CE,a software implementation of RDMA.Soft Ro CE is implemented by software,and the hardware uses ordinary Ethernet network interface cards.Compared with the hardware RDMA solution,the performance of Soft Ro CE is poor,but has the advantage of being able to communicate with RDMA network interface cards using ordinary Ethernet network interface cards.In this thesis,the overall process of Soft Ro CE data transmission was analyzed.For the problems of low throughput,large transmission delay,and high CPU occupancy in the data transmission process of Soft Ro CE,solutions were proposed and experiments were designed to prove the feasibility of solutions.In this thesis,the following works were carried out around the performance optimization and security enhancement issues of Soft Ro CE:1.Soft Ro CE requires one additional CPU copy during data transmission.To address this problem,a zero-copy Soft Ro CE solution for hotspot data transmission was proposed.Firstly,the overall design of the program was performed.For the frequently used hotspot data,the fixed data buffer approach can eliminate one CPU copy in the data sending process of Soft Ro CE and achieve zero-copy of the hotspot data.Experiments were designed to test the throughput and transmission delay of this solution.The test results show that this scheme can not only improve the throughput,but also reduce the data transmission delay,which can effectively improve the performance of hotspot data transmission system.2.The frequent polling in the packet receiving mechanism leads to high CPU usage.To address this problem,an optimized design method of packet receiving mechanism based on batch processing was proposed.Firstly,the scheme was designed and implemented.In the implementation,multiple work requests were merged,and multiple work completions were merged.The polling packet receiving mechanism was optimized by CTX＿POLL＿BATCH to batch process work completion messages.A comparison experiment was designed to test the CPU occupancy,throughput and latency before and after the optimization.The experimental results show that the optimized scheme can not only significantly reduce CPU occupancy,but also causes little impact on system throughput and latency performance.3.By analyzing the communication process using Send/Recv operation in UD mode,a security issue was found that could be exploited.An authentication scheme was proposed for the problem that the receiving queue resources may be maliciously occupied in UD mode.Authentication of both senders and receivers was accomplished by calculating the Hash value of the random number PSN and the shared secret value Q＿Key.The overall procedure of the authentication scheme was designed.The security and efficiency of the solution was analyzed.The experimental results show that the authentication scheme proposed in this thesis can effectively filter malicious information and improve the security of Soft Ro CE.