Architecture of Virtual Machines Summarized by Michael Riera 9 17 2011 University of Central Florida CDA5532 Papers in discussion Recommendations for Virtualization Technologies in High Performance Computing Nathan Regola Center for Research Computing Notre Dame Jean Christophe Ducom Center for Research Computing Notre Dame The Architecture of Virtual Machines James E Smith University of Wisconsin Madison Ravi Nair IBM T J Watson Rsearch Center Understanding Performance Interference of I O Workload in virtualized Cloud Environments Xing Pu Ling Liu Yiduo Mei Sankaran Sivathanu Younggyun Koh Calton Pu Georgia Tech Beijing Institute of Technology P R China Xi an Jiaotong University P R China Agenda Purpose What does it mean to Virtualize Abstraction layers Interfaces Classic Architecture Cross Compiling Process VM Hosted Non Hosted VM System VM aka VMM Hypervisors Terminology Purpose The purpose of this paper is to give the reader a fundamental broad knowledge on the main components of a Virtual Machine VM and its interaction with the Hardware This papers give a high level description of what abstracting virtualizing processes OS the hardware and the ISA layer from a running process Virtualizing Virtualizing provides a way to Multiplex under utilized resources such as CPU Cycles Memory Storage Access Allow multiple users to compute on the same hardware as if they were in sole control A way to translate an instruction set architecture ISA to another ISA without needing to recompile or migrate High level applications Example Virtualizing software uses the file abstraction as an intermediate step to provide mapping between the virtual and real disks Common Computer Architecture Process System VM A process VM is a virtual platform that executes an individual process Its created when needed and terminated when process is completed Provides a an ABI or API environment Cross Compiling Ex Sun Microsystem Java VM Microsoft Common Language NET A system VM aka Virtual Machine Monitors Provides a complete persistent system environment that supports an OS along with its many user process The VMM emulates the hardware ISA Provides resource management for multiple VMs A process or system that runs on the VM is coined as a guest The Platform that supports the VM is coined as the host The virtualizing software that implements a process VM is typically called runtime software Process System VM Process System VM Emulator and dynamic binary translators Interpret An interpreter program that fetches decodes and emulates the execution of a guest instruction too SLOW Dynamic binary translator Converts guest instructions to host instructions in blocks rather than instruction by instruction and saves them for reuse in a software cache Process System VM Process System VM Co designed VM Motivation Functionality and portability For more specific proprietary ISA that are uncomment Appears as hardware the VMM resides in a region of memory concealed from all conventional software Includes a binary translator Process System VM