Docker Live Migration For Kubernetes

Docker container are widely used as infrastructure for building PaaS(Platform-as-aService)and SaaS(Software-as-a-Service)clouds due to the small memory footprint,fast startup times and high performance offered by container virtualization.At the same time,Kubernetes has become the most widely used container management platform.For such container clouds,various management service for the cloud need to be revisited because they are fundamentally different from VM clouds.Migration plays a very important role in host maintenance,load balancing,service upgrade as one of the most common operations of cloud service providers.However,there is currently no solution for live-migration of Docker containers for data center.A container live migration mechanism for Kubernetes,PodMS is presented.PodMS provides container live migration service for Kubernetes,which supports Kubernetes by enabling Pod live migration.First,in order to reduce the migration data size,PodMS completes image migration and filesystem migration with full consideration of characteristics of Docker.In image migraion,we use cache matching to reduce the migration data size.And in filesystem migration,we migrate the modified files and file placeholders instead of all files.Second,PodMS minimizes the service downtime by combining CRIU-based memory migration together with the improved pre-copy approach.At last,PodMS enables the migration of Pods in Kubernetes by adding a Virtual IP Table which determines the IP address of the Pod in Pod live migration.PodMS provides a complete Pod live-migration which can reduce image data transmission by 51% by cache matching.In filesystem migration,overlay?aufs and overlay2 can reduce data transmission by 37%,30.1% and 24%.In memory migration,the number of iterations required can be reduced by up to 50% compared to the traditional precopy approach;The Pod live migration process takes 1~2 minutes,and the service downtime is less than 1 second.