操作体统实习经验介绍.pptVIP

Automatic Scaling of Internet Applications for Cloud Computing Services Zhen Xiao, Qi Chen, and Haipeng Luo May 2013 To appear in IEEE Transactions on Computers 0 Outlines 0 Outlines Benefits of Cloud Computing Auto-scaling: Cloud computing allows business customers to scale up and down their resource usage based on needs Hypervisor Hypervisor Hypervisor Hypervisor L7 Switch Myth #1: Cloud computing provides infinite resource on demand --- Reality: just statistical multiplexing Myth about Cloud Computing Hypervisor Hypervisor Hypervisor Hypervisor L7 Switch When and where to start a VM for an application? Goals of Scheduling Achieve good demand satisfaction The percentage of application demand that is satisfied should be maximized when a large number of applications experience their peak demand around the same time. Support green computing the number of servers used should be minimized as long as they can still satisfy the needs of all VMs. Idle servers can be turned off to save energy. Goals of Scheduling 0 Outlines Auto scaling in Amazon EC2 -- Scalr For one application Load balancing Google AppEngine Support Java Python Secure sandbox environment has strict limitations Can not support existing applications Microsoft Windows Azure Applications should be stateless Users maintain the number of Instances Load balancing Related Work 0 Outlines System Architecture Appl info Xen Hypervisor Dom 0 Usher LNM Dom U Xen Hypervisor Dom 0 Usher LNM Dom U Xen Hypervisor Dom 0 Usher LNM Dom U Usher CTRL Application Scheduler Plugin Monitor Appl placement Algorithm adjustment Load distribution Requests … Switch Dispatcher Appl info Instance list Request counter Reqs Complicated applications can take a long time to finish all the initializations (several minutes) Suspend Resume Resumption time is independent of the start up time It depends on how fast the server can read the suspended VM file from the disk, which is quite short (several seconds) with modern disk technol