Virtual Workspaces in the Grid Kate Keahey Argonne National Laboratory Ian Foster, Tim Freeman, Xuehai Zhang, Daniel Galron

09/01/05Kate Keahey, Europar 2005 The Grid Metaphor How do we store energy? How do we charge for energy? How do we reliably deliver energy? What happens if a power station fails? How do we ensure quality of service? What elements make for a safe and efficient power Grid? How do we make sure that supply meets demand? Grid Computing is much harder: heterogeneous and multi-dimensional

09/01/05Kate Keahey, Europar 2005 The Missing Link in Grid Computing l We need to define mechanisms for and dynamic deployment and management of remote environments Ideal environment is deployed magic happens l Requirements: u Flexibly define an environment l The more we can customize it, the more useful it is u Deploy and manage such environments l Can such environments be deployed securely? l How fast/dynamic can this deployment be? l How can I control resources allocated to such an environment? Dream up an ideal environment

09/01/05Kate Keahey, Europar 2005 Virtual Workspaces l Virtual Workspaces: environments that can be made available dynamically the Grid with well- understood properties l Examples: u A TeraGrid node with well-defined software environment and adjustable access and sharing policies u A physical cluster booted to a desired configuration (e.g. Cluster on Demand) u An ATLAS node dynamically configured using Pacman u A virtual machine configured to represent a specific environment whose resource consumption can be controlled

09/01/05Kate Keahey, Europar 2005 Virtual Machines as Workspaces l Virtual Machines u Highly customizable software configuration u Enforcement properties l Grid 2004 paper: Dynamic environments in the Grid l F. Cappello & lab: Comparison of different hypervisors u Pausing, serialization, migration u Performance: LXVU SPEC INT2000 (score) LXVU Linux build time (s) LXVU OSDB-OLTP (tup/s) LXVU SPEC WEB99 (score) SOSP 2003 paper: Xen and the Art of Virtualization

09/01/05Kate Keahey, Europar 2005 Workspace Template Aspects l Environment Aspect (workspace meta-data) u Generic information l Name, time to live, etc. u Software partition information l Software description: OS, OSG configuration, application partition, etc. l Software meta-data is bundled with the actual software and attested by its issuer u Services: ssh, GRAM, pre-configured job u Deployment independent l Resource allocation request (deployment time) u Memory, disk, networking, etc. l See GGF JSDL standard u On deployment the actual resource allocation information becomes available

09/01/05Kate Keahey, Europar 2005 Atomic Workspaces and Virtual Clusters l Atomic workspace u One or more homogeneous workspaces l The only differences are in names l Cluster/aggregate workspace u A set of interdependent heterogeneous workspaces l Example: a headnode and a set of worker nodes u Interdependencies of metadata are expressed through tags and pointers

09/01/05Kate Keahey, Europar 2005 Deploying Workspaces in the Grid l Define workspace environment l Manage workspace l Negotiate workspace deployment characteristic Workspace Wizard (VW Factory) Workspace Management Service (VW Repository) Workspace Service (VW Manager) request a workspace workspace meta-data manage workspace environment workspace metadata Workspace terminate workspace deployment negotiate workspace deployment manage/monitor/renegotiate workspace deployment manage activities within the workspace

09/01/05Kate Keahey, Europar 2005 Current Implementation l Current prototype using Globus Toolkit 4 u Leveraging standard Grid Service features such as lifetime management l Workspace Wizard u Returns workspace meta-data u Very rudimentary implementation l Workspace Serivce u Create: takes workspace meta-data and a deployment descriptor u Manage: l renegotiate resource allocation (moving towards a WS- Agreement model) l Also traditional Grid Service management: TTL, etc. u Destroy l Different options: pause, shutdown or destroy

09/01/05Kate Keahey, Europar 2005 How dynamic is the deployment? l Automatic u Protocol-based u Moving towards better articulation of migration u Renegotiation of resource allocation l How fast is this deployment? u Deployment of workspace for EMBOSS suite: l Manual: ~45 minutes l Based on pre-configured Vmware VMs: ~6 minutes l Based on pre-configured Xen VM: < 1 second l How much overhead does workspace deployment add over what we have today?

09/01/05Kate Keahey, Europar 2005 Workspace Service: Individual Workspaces l Using a paused VM allowed us to save on initiation time a)GRAM job execution b)GRAM job execution in a paused Xen VM c)job execution in a booted Xen VM (pre-configured job)

09/01/05Kate Keahey, Europar 2005 Workspace Service: Virtual Clusters

09/01/05Kate Keahey, Europar 2005 Deploying Workspaces Across Technologies l Basic node configuration (+/-boot from image) u Cluster on Demand, PXE, bcfg u On the order of many minutes (~30 minutes) l Refining configuration, creating access u Dynamic account with workspace service: < 1s (mostly GT4 request processing time) u Refining Installation: ~2 hours to configure an ATLAS node using Pacman l Virtual machines u Deploying images l Xen: ~100 ms l VMware Workstation: ~ several seconds

09/01/05Kate Keahey, Europar 2005 Nested Workspaces Physical machine procure hardware program … VM Hypervisor/OS deploy hypervisor/OS workspace VM deploy VM workspace (with hypervisor/OS)

09/01/05Kate Keahey, Europar 2005 Computational Grids Hypervisor 1Hypervisor 2TeraGrid Configuration Grid Power Station Grid Protocols Clients

09/01/05Kate Keahey, Europar 2005 Conclusions l We need mechanisms for dynamically deploying and managing environments in the Grid l Workspaces are a fundamental building block of a Grid environment u Workspaces are implemented using wide variety of technologies l VMs are a highly promising one: a computon for the Grid u Workspace aspects l Deployment-independent environment definition l Deployment-time policy and enforcement negotiation l Many challenges remain u Security and deployment issues u Protocols, protocols, protocols u Leveraging the opportunities