Migrating operating system instances across distinct physical hosts is a useful tool for administrators of data centers and clusters: It allows a clean separation between hardware and software, and facilitates fault management, load balancing, and low-level system maintenance. By carrying out the majority of migration while OSes continue to run, we achieve impressive performance with minimal service downtimes; we demonstrate the migration of entire OS instances on a commodity cluster, recording service downtimes as low as 60ms. We show that that our performance is sufficient to make live migration a practical tool even for servers running interactive loads. In this paper we consider the design options for migrating OSes running services with liveness constraints, focusing on data center and cluster environments. We introduce and analyze the concept of writable working set, and present the design, implementation and evaluation of highperformance OS migration built on top of the Xen VMM. 1

-late. Often there is no feasible method to recharge motes, so energy is a precious resource. Once deployed, a network must be reprogrammable although physically unreachable, and this reprogramming can be a significant energy cost. We present Maté, a tiny communication-centric virtual machine designed

virtual machine and logging below the virtual machine. This allows ReVirt to replay the system’s execution before, during, and after an intruder compromises the system, even if the intruder replaces the target operating system. ReVirt logs enough information to replay a long-term execution of the virtual

Abstract As virtual machine emulators have become commonplace in the analysis of malicious code, malicious code has started to fight back. This paper describes known attacks against the most widely used virtual machine emulators (VMware and VirtualPC). This paper also demonstrates newly discovered

, while retaining the ability to run side-by-side with normal applications on a generalpurpose computing platform. Terra achieves this synthesis by use of a trusted virtual machine monitor (TVMM) that partitions a tamper-resistant hardware platform into multiple, isolated virtual machines (VM), providing

this through the use of a virtual machine monitor. Using this approach allows us to isolate the IDS from the monitored host but still retain excellent visibility into the host's state. The VMM also offers us the unique ability to completely mediate interactions between the host software and the underlying

virtualization extensions to the instruction set that can be utilized to write relatively simple virtual machine monitors. The Kernel-based Virtual Machine, or kvm, is a new Linux subsystem which leverages these virtualization extensions to add a virtual machine monitor (or hyper-visor) capability to Linux

A virtual machine (VM) is an efficient, isolated duplicate of a real machine [PG74]. Duplicate: VM should behave identical to the real machine ➜ programs cannot distinguish between execution on real or virtual hardware ➜ except for: ➜ less resources available (and potentially different between

In this paper we develop a model which represents the addressing of resources by processes executing on a virtual machine. The model distinguishes two maps: the ~-map which represents the map visible to the operating system software running on the virtual machine, and the f-map which is invisible

1 2 LVM, the lazy virtual machine 1