From Sandbox to Playground: Virtual Environments and Quality of Service in the Grids

1. From Sandbox to Playground: Virtual Environments and Quality of Service in the Grids Kate Keahey keahey@mcs.anl.gov Argonne National Laboratory

2. What are Grids? • Power Grid analogy: remote computing power can be accessible from your laptop in much the same way as electricity is delivered to your home Kate Keahey

3. How do Grids work today? • From Grid Services… • Discover remote resources • Start jobs on remote resources • Authenticate and authorize users and other entities • Transfer data • Globus Toolkit: a de facto standard in Grid technologies • … to commodity Grid usage • Combining and automating the use of basic Grid services • Utility computing paradigm • Provide reliable, adaptive, QoS-based execution of specific tasks Kate Keahey

4. Access Grid: enable people, presentation software and programs to interact Computational Grid: use access to powerful resources to run a genome analysis service Data Grid: combine distributed data and access storage within one similation Experiment Grid: combine multiple technologies in support of an experiment Grid Capabilities Today Kate Keahey

5. First, a little bit of theory… “Resource sharing & coordinated problem solving in dynamic, multi-institutional virtual organizations” Single sign-on creates a decentralized Grid domain within which Grid entities can act on behalf of the user Kate Keahey

6. Grid clients • create environments • Application developers • obtain the right configuration • Grid administrators • resolve conflicts! …now practice More resources per user, more users per resource, more environments per resource…. How do we scale? Kate Keahey

7. What do we need? • Quality of Service • Sandbox a Grid computation • Reliable enforcement of policy-driven resource usage • Applications in experimental sciences, fair resource sharing, etc. • Quality of Life • Dynamic capabilities • Dynamically creating and managing remote execution environments • Dynamically configuring such environments • Easily moving in a Grid as resources come and go • Automated, hands-off Grid infrastructure Kate Keahey

8. How do we satisfy those needs? • Dynamic behavior: missing services • Creating and managing remote execution environments dynamically • Customizing such environments • Ontologies and protocols • Standardized descriptions can be processed dynamically by various Grid entities • Policy-adapting protocols will equip the system with ability to respond to needs automatically • Tools to obtain descriptions of these things easily and automatically Kate Keahey

9. Virtual Workspaces Grid client Interface Grid clients Execution state Virtual Workspace Software and file configuration state Protection and enforcement environment Grid Middleware Interface Grid middleware interface Virtual resource configuration • VWs are represented by an ontology description • Potentially integrating community policy • They can be implemented using different technologies • They can be customized to the user needs and deployed in the Grid Kate Keahey

10. Properties of Virtual Workspaces • Dynamic creation • Inherent property of Grid computation • Avoiding a maintenance nightmare (automate administration) and potential security hazard • Dynamic configuration • To reflect changing policies in the Grid (implement agreements) • Strong protection environment • Otherwise users won’t trust sites and sites won’t trust users • Fine-grain enforcement • Configurable architecture, software, environment • Application software/libraries/licenses • Configurable environment • Running 32-bit programs on 64-bit architectures • Running a required version of the OS (Fedora vs. RH9) • Potentially even execution state Kate Keahey

11. request use existing VW deploy & suspend VWs in the Grids VW Factory create new VW VW EPR Create VW VW Repository inspect and manage Client Resource VW Manager VW start program Kate Keahey

12. VW Services • Factory • Creates VW in terms of the implementation • e.g., VM image, pacman chache+ • May create based on an already created VW • Writes/configures access policy • May allow negotiation • VW Repository • Access to state describing a VW • Allows inspection, management, implementation-specific termination, potentially renegotiation, etc. • Soft-state lifetime management ensures termination • VW Manager • Lightweight infrastructure deploying VMs Kate Keahey

13. How can I obtain VWs? • Through automatic negotiation and establishing agreements with the community • What is an agreement? • Relationship between parties • dynamically-established and dynamically-managed • Terms • Functional, e.g., a service I can perform • Non-functional, e.g., performance, availability, etc. • Noteworthy Agreement Properties • Simple, decentralized way of expressing aggregate or proprietary policies in the system • Allow providers to gauge demand • Ephemeral, periodic, fine-grained, modifiable policy • WS-Agreement, GRAAP-WG, Global Grid Forum • Currently under public comment: see www.gridforum.org Kate Keahey

14. Implementing and Configuring Virtual Workspaces • Potential Implementation Groups • Unix accounts and Unix account tools • setrlimit, DSRT, chroot, chown, and others • Sandboxes • VServer, protection and fine-grain enforcement • Virtual Machines • VMware, Xen, and others • Deployment & configuration tools • Pacman & pacman cache • See also: • Grid 2004: “From Sandbox to Playground: Dynamic Virtual Environments in the Grid” Kate Keahey

15. Comparing VW Implementations • Unix accounts • Pros: efficient, ubiquitous • Cons: very limited functionality • Needs to be used in conjunction with other technologies • Pacman, additional system enforcement tools • Prototype available (GT 3.2) • http://www-unix.mcs.anl.gov/~keahey/DS/DynamicSessions.htm • Currently on the way to become a GT4 service • Sandboxes • Pros: efficient, fine-grain enforcement, typically very lightweight • Cons: limited state enforcement • Need to be used in conjunction with other technologies Kate Keahey

16. Comparing VW Technologies (cntd) • Virtual Machines • Pros: • Flexibility (run linux on linux, 32 on 64-bit, etc.) • Enhanced security, audit forensics, etc. • Great user state management • Freezing/migration • Customized environment • A promising distribution/deployment tool • Cons: • Potential for being less efficient (emulation) • Potential for resource overhead • Poor implementation of sharing, relatively little enforcement (but can be combined with other technologies for enforcement) • Maturity issues • The potential is excellent, but needs more work Kate Keahey

17. The Need for Speed Comparison using the Fusion EFIT application Kate Keahey

18. Other efficiency concerns • Startup time • Resource usage overhead • Memory use: VMware: 24MB + 1 MB per 32 MB memory allocated • Disk use: VMware large Kate Keahey

19. Enforcement Capabilities Kate Keahey

20. Virtual is the New Real! • Virtual machines are a very interesting option for the Grid • Excellent usability potential: • Configurability, enhanced security, state management, replication, enforcement… • Even potential as distribution tool! • Excellent potential for optimizations • Performance, resource usage, access to specialized hardware, etc. are not so bad, especially with new technologies like Xen • Some maturity issues • Do benefits outweigh challenges? Kate Keahey

21. How does it work in practice? • Recent project: combining VMs and Grids to create a platform for bioinformatics applications • Some of the conclusions: • Use of virtual machines can significantly broaden the resource base • Saves installation time • EMBOSS installation: ~45 minutes • Deploying a 2GB VM image: ~6.5 minutes • Peace of mind: priceless! • Enforcement capabilities • Depend on the implementation but are generally better than what we have now • SC04 poster: • “Quality of Life in the Grids: VMs meet Bioinformatics Applications”, T. Freeman and D. Galron Kate Keahey

22. How can VWs change the Grid? • Challenges to the established Grid model • Security challenges • Networking challenges • And many, many others… • Issue of responsibility • Who vets a workspace? • Who is responsible for its “good behavior”? • The role of VOs is going to grow • VO might take on additional responsibilities • Administers and maintains VMs, certification authority, could potentially stop suspect VMs, is to blame if something happens… • Should the VO be a legal entity? • Do VOs have the resources to do that? • Are VOs going to become too heavyweight? • What are the trade-offs and a healthy balance? Kate Keahey

23. Virtual Playgrounds • Define a virtual Grid in terms of requirements • Virtual workspaces • Potentially networking requirements • Other services • Provide mechanisms to create a Grid • Provide services for the deployment of such “virtual playgrounds” on real resources • Ephemeric Grids built for a special purpose: • Family is getting together to decide when to spend Xmas • Scientists getting up a Grid for the purposes of a specific experiment run • A game tournament • A scientific simulation that gets discarded or interrrupted but can potentially be restored later • Towards a true utility computing model Kate Keahey

24. Conclusions • Addressing QoS and QoL is critical for the utility computing model of Grids • Unglamorous but necessary tasks • Combating complexity, improving scalability • Without it flexibly moving between resources on the Grid is very hard • Current technological advances make this model ever closer to reality • A breakthrough is required in terms of usability • Virtual machines fit the bill • Virtual is the new Real! • To find out more: www.mcs.anl.gov/~keahey Kate Keahey