Virtual Workspaces in the Grid Kate Keahey [email protected] Argonne National Laboratory Ian Foster, Tim Freeman, Xuehai Zhang, Daniel Galron.

Virtual Workspaces in the Grid

Kate [email protected]

Argonne National Laboratory

Ian Foster, Tim Freeman, Xuehai Zhang, Daniel Galron

09/01/05 Kate 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

09/01/05 Kate Keahey, Europar 2005

The Missing Link in Grid Computing We need to define mechanisms for and dynamic

deployment and management of remote environments

Ideal environment is deployed

magichappens

Requirements: Flexibly define an environment

The more we can customize it, the more useful it is

Deploy and manage such environments Can such environments be deployed securely? How fast/dynamic can this deployment be? How can I control resources allocated to such an environment?

Dream up an ideal environment

09/01/05 Kate Keahey, Europar 2005

Virtual Workspaces

Virtual Workspaces: environments that can be made available dynamically the Grid with well-understood properties

Examples: A TeraGrid node with well-defined software environment

and adjustable access and sharing policies A physical cluster booted to a desired configuration

(e.g. Cluster on Demand) An “ATLAS node” dynamically configured using Pacman A virtual machine configured to represent a specific

environment whose resource consumption can be controlled

09/01/05 Kate Keahey, Europar 2005

Virtual Machines as Workspaces

Virtual Machines Highly customizable software configuration Enforcement properties

Grid 2004 paper: “Dynamic environments in the Grid” F. Cappello & lab: Comparison of different hypervisors

Pausing, serialization, migration Performance:

L X V USPEC INT2000 (score)

L X V ULinux build time (s)

L X V UOSDB-OLTP (tup/s)

L X V USPEC WEB99 (score)

0.00.10.20.30.40.50.60.70.80.91.01.1

SOSP 2003 paper: “Xen and the Art of Virtualization”

09/01/05 Kate Keahey, Europar 2005

Workspace Template Aspects Environment Aspect (workspace meta-data)

Generic information Name, time to live, etc.

Software partition information Software description: OS, “OSG configuration”, “application partition”,

etc. Software meta-data is bundled with the actual software and attested by

its issuer

Services: ssh, GRAM, pre-configured job Deployment independent

Resource allocation request (deployment time) Memory, disk, networking, etc.

See GGF JSDL standard

On deployment the actual resource allocation information becomes available

09/01/05 Kate Keahey, Europar 2005

Atomic Workspaces and Virtual Clusters

Atomic workspace One or more homogeneous workspaces

The only differences are in names

Cluster/aggregate workspace A set of interdependent heterogeneous

workspaces Example: a headnode and a set of worker nodes

Interdependencies of metadata are expressed through tags and pointers

09/01/05 Kate Keahey, Europar 2005

Deploying Workspaces in the Grid

Define workspace environment

Manage workspace

Negotiate workspace deployment characteristic

WorkspaceWizard

(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

09/01/05 Kate Keahey, Europar 2005

Current Implementation Current prototype using Globus Toolkit 4

Leveraging standard Grid Service features such as lifetime management

Workspace Wizard Returns workspace meta-data Very rudimentary implementation

Workspace Serivce Create: takes workspace meta-data and a deployment

descriptor Manage:

renegotiate resource allocation (moving towards a WS-Agreement model) Also traditional Grid Service management: TTL, etc.

Destroy Different options: pause, shutdown or destroy

09/01/05 Kate Keahey, Europar 2005

How dynamic is the deployment?

Automatic Protocol-based Moving towards better articulation of migration Renegotiation of resource allocation

How fast is this deployment? Deployment of workspace for EMBOSS suite:

Manual: ~45 minutes Based on pre-configured Vmware VMs: ~6 minutes Based on pre-configured Xen VM: < 1 second

How much overhead does workspace deployment add over what we have today?

09/01/05 Kate Keahey, Europar 2005

Workspace Service: Individual Workspaces

Using a paused VM allowed us to “save” on initiation time

8

8

8

0.7

0.7 1.7

0.8

0.8

0 2 4 6 8 10 12

a)

b)

c)

job startup scenario

time (in seconds)

VM setup

VM boot

job setup

GRAM job

a) GRAM job executionb) GRAM job execution in a paused Xen VMc) job execution in a booted Xen VM (pre-configured job)

09/01/05 Kate Keahey, Europar 2005

Workspace Service: Virtual Clusters

09/01/05 Kate Keahey, Europar 2005

Deploying Workspaces Across Technologies

Basic node configuration (+/-boot from image) Cluster on Demand, PXE, bcfg On the order of many minutes (~30 minutes)

Refining configuration, creating access Dynamic account with workspace service: < 1s

(mostly GT4 request processing time) Refining Installation: ~2 hours to configure an ATLAS

node using Pacman Virtual machines

Deploying images Xen: ~100 ms VMware Workstation: ~ several seconds

09/01/05 Kate Keahey, Europar 2005

Nested Workspaces

Physical machineprocure hardware

program program program

…VM

Hypervisor/OSdeploy hypervisor/OS workspace

VM VMdeploy VM workspace (with hypervisor/OS)

09/01/05 Kate Keahey, Europar 2005

Computational Grids

Hypervisor 1 Hypervisor 2 TeraGrid Configuration

Grid Power Station

Grid Protocols

Clients

09/01/05 Kate Keahey, Europar 2005

Conclusions We need mechanisms for dynamically deploying and

managing environments in the Grid Workspaces are a fundamental building block of a Grid

environment Workspaces are implemented using wide variety of

technologies VMs are a highly promising one: a “computon” for the Grid

Workspace aspects Deployment-independent environment definition Deployment-time policy and enforcement negotiation

Many challenges remain Security and deployment issues Protocols, protocols, protocols Leveraging the opportunities