1. The vMatrix: A Network Of Virtual Machine Monitors For Dynamic Content Distribution Amr A. Awadallah Mendel Rosenblum {aaa,mendel}@cs.stanford.edu Stanford University – Computer Systems Lab – WCW 2002

2. Stanford University – CSL – WCW 2002 What is The vMatrix?

3. Stanford University – CSL – WCW 2002 Problem Statement Motivation: To enable distribution of dynamic content. (40% of web requests) Definition: Dynamic content is web pages which are constructed by programs that execute on the server at the time a request is made. (e.g. http://maps.yahoo.com)

4. Stanford University – CSL – WCW 2002 Advantages of Distribution Faster Response Time Higher Availability Absorbing Flash Crowds Network Bandwidth Savings Lower Total Cost of Ownership

5. Stanford University – CSL – WCW 2002 Today Is Static Mirroring

6. Stanford University – CSL – WCW 2002 Dynamic Content Distribution

7. Stanford University – CSL – WCW 2002 Two Tier Architecture

8. Stanford University – CSL – WCW 2002 Main Problem It is very hard to copy services due to all the dependencies that code has on system libraries, third-party modules, operating systems, and server hardware. Amended Motivation: To enable distribution of server code with minimal application, code, or operating system changes (i.e. backward compatibility with existing implementations)

9. Stanford University – CSL – WCW 2002 Virtual Machine Monitors Virtual Machine Monitor Real Machine (CPU, Memory, Disks, Network) Virtual Machine 1: vCPU, vMem, vDisk, vNet OS1: Windows 2000 Virtual Machine 2: vCPU, vMem, vDisk, vNet OS2: Linux MySQL, Apache Oracle, IIS

10. Stanford University – CSL – WCW 2002 Proposed Solution A network for delivering virtual machines (VMs) between real machines (RMs) running the virtual machine monitor (VMM) software.

11. Stanford University – CSL – WCW 2002 Distinguishing Advantage Backward Compatibility Disadvantage VM files are very large (order of gigabytes)!

12. Stanford University – CSL – WCW 2002 Challenges: Mobility (NAT) VMM RM VM Agent VM1VM2 192.168.1.10 NAT/LB Internet 64.58.77.28 DNS maps.yahoo.com 64.58.77.28

13. Stanford University – CSL – WCW 2002 Challenges: Security (VPNs) VMM VM1VM2 RM VM Agent VPN Intranet DNS 192.168.1.10 Firewall Internet 64.58.77.28 172.21.162.9 c009.proxy.yahoo.com maps.yahoo.com 64.58.77.28 NAT/LB Internet 64.58.77.28

14. Stanford University – CSL – WCW 2002 Two Tier Challenges Response Time FRONT ENDBACK END N1N1 FRONT END N1N1 BACK END N2N2 Perception!

15. Stanford University – CSL – WCW 2002 Two Tier Challenges Availability FRONT END BACK END

16. Stanford University – CSL – WCW 2002 Two Tier Challenges Replication BACK END FRONT END

17. Stanford University – CSL – WCW 2002 Related Work Active Proxy Caches (ICAP, Active cache, OPES) App Servers (WebSphere, Dynamo, WebLogic) Java Virtual Machine (J#/C#/.Net) Light Weight OSes (Denali, Xenoservers) OS Virtualization (Ensim, Ejasent, EXETender) Portable Channel Representations (e.g. RPMs)

18. Stanford University – CSL – WCW 2002 Current & Future Work Global Server Placement Optimization VM Scheduling per RM Server Multiplexing Compute Utility (The Collective) ROC: Virtual Hot Standbys Internet Scale Applications Characteristics

19. Stanford University – CSL – WCW 2002 Conclusion Using off the shelf technologies available today it is possible to build a network for delivering virtual machines between real machines hence solving the dynamic content distribution problem without requiring significant architectural changes.