With the evolution of the communication standards, Software Defined Radio (SDR) is faced with an increasingly important problem to balance more and more complex wireless communication algorithms against relatively lim...With the evolution of the communication standards, Software Defined Radio (SDR) is faced with an increasingly important problem to balance more and more complex wireless communication algorithms against relatively limited processing capability of hardware. And, the competition for computing resources exacerbates the problem and increases time-delay of SDR system. This paper presents an integrated optimization method for the real-time performance of SDR on Linux OS (operating system). The method is composed of three parts: real-time scheduling policy which ensures higher priority for SDR tasks, CGROUPS used to manage and redistribute the computing resources, and fine-grade system timer which makes the process preemption more accurate. According to the experiments, the round-trip data transfer latency decreases low enough to meet the requirement for TD-SCDMA via the application of the method.展开更多
Container-based virtualization isbecoming increasingly popular in cloud computing due to its efficiency and flexibility.Resource isolation is a fundamental property of containers.Existing works have indicated weak res...Container-based virtualization isbecoming increasingly popular in cloud computing due to its efficiency and flexibility.Resource isolation is a fundamental property of containers.Existing works have indicated weak resource isolation could cause significant performance degradation for containerized applications and enhanced resource isolation.However,current studies have almost not discussed the isolation problems of page cache which is a key resource for containers.Containers leverage memory cgroup to control page cache usage.Unfortunately,existing policy introduces two major problems in a container-based environment.First,containers can utilize more memory than limited by their cgroup,effectively breaking memory isolation.Second,the Os kernel has to evict page cache to make space for newly-arrived memory requests,slowing down containerized applications.This paper performs an empirical study of these problems and demonstrates the performance impacts on containerized applications.Then we propose pCache(precise control of page cache)to address the problems by dividing page cache into private and shared and controlling both kinds of page cache separately and precisely.To do so,pCache leverages two new technologies:fair account(f-account)and evict on demand(EoD).F-account splits the shared page cache charging based on per-container share to prevent containers from using memory for free,enhancing memory isolation.And EoD reduces unnecessary page cache evictions to avoid the performance impacts.The evaluation results demonstrate that our system can effectively enhance memory isolation for containers and achieve substantial performance improvement over the original page cache management policy.展开更多
文摘With the evolution of the communication standards, Software Defined Radio (SDR) is faced with an increasingly important problem to balance more and more complex wireless communication algorithms against relatively limited processing capability of hardware. And, the competition for computing resources exacerbates the problem and increases time-delay of SDR system. This paper presents an integrated optimization method for the real-time performance of SDR on Linux OS (operating system). The method is composed of three parts: real-time scheduling policy which ensures higher priority for SDR tasks, CGROUPS used to manage and redistribute the computing resources, and fine-grade system timer which makes the process preemption more accurate. According to the experiments, the round-trip data transfer latency decreases low enough to meet the requirement for TD-SCDMA via the application of the method.
基金supported by the National Key Research and Development Program (2022YFB4500704)the National Natural Science Foundation of China (Grant Nos.62032008,62232012 and 62232011).
文摘Container-based virtualization isbecoming increasingly popular in cloud computing due to its efficiency and flexibility.Resource isolation is a fundamental property of containers.Existing works have indicated weak resource isolation could cause significant performance degradation for containerized applications and enhanced resource isolation.However,current studies have almost not discussed the isolation problems of page cache which is a key resource for containers.Containers leverage memory cgroup to control page cache usage.Unfortunately,existing policy introduces two major problems in a container-based environment.First,containers can utilize more memory than limited by their cgroup,effectively breaking memory isolation.Second,the Os kernel has to evict page cache to make space for newly-arrived memory requests,slowing down containerized applications.This paper performs an empirical study of these problems and demonstrates the performance impacts on containerized applications.Then we propose pCache(precise control of page cache)to address the problems by dividing page cache into private and shared and controlling both kinds of page cache separately and precisely.To do so,pCache leverages two new technologies:fair account(f-account)and evict on demand(EoD).F-account splits the shared page cache charging based on per-container share to prevent containers from using memory for free,enhancing memory isolation.And EoD reduces unnecessary page cache evictions to avoid the performance impacts.The evaluation results demonstrate that our system can effectively enhance memory isolation for containers and achieve substantial performance improvement over the original page cache management policy.