The GT 4 GRAM Service
Sam Meder
(meder@mcs.anl.gov)
Middleware Workshop
Service: GT4 GRAM
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GRAM provides a service interface to compute
resources (clusters etc).
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Job submission
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Staging
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Discovery
Not yet available (first alpha at end of month)
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URL: http://www.globus.org/toolkit
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License: Globus Toolkit Public License (BSD style)
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Support: Will become fully supported with the
release of GT 4.0
SOA Model:WS-RF
Design Goals
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Performance
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Scalability
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Throughput
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(Latency)
Modularity
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Staging
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Delegation
Service Operations (Factory)
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WS-ResourceProperties operations
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createManagedJob()
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Description:
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IN: Job description
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OUT: EPR for created job resource
Service Operations (Service)
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WS-ResourceProperties operations
WS-ResourceLifetime operations
WS-BaseNotification NotificationProducer
operations
start()
Description:
‹ IN: void
‹ OUT: current state of job
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Performance vs. GT3 GRAM
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Reduced number of roundtrips
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Single hosting environment
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Modular: What you don’t use you don’t pay
for
Event based scheduler/job monitoring
What do you use to build your service?
(i.e. How ‘standard’ is your service?)
NB:A low score means less risk & more mainstream
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Widely Implemented Standard Specification (1pt)
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Implemented draft specification (2pt)
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WS-Addressing
Non-implemented proposal (5pt)
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WS-Resource Framework, WS-Notification
Implemented proposal (4pt)
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WS-Security
Implemented draft specification (3pt)
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SOAP, WSDL, etc (where to start?)
The service itself is a proposal?
Concept (6pt)
TOTAL: (find this a bit silly)
Service Dependencies
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What else does your service depend on
(i.e. external dependencies)?
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GT4 Core which in turn depends on a host
of third party technologies (RDBMs etc)
What does your implementation depend
on?
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Languages: Java, C, Perl
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Container type: Web container/servlet
AAA & Security
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What authentication mechanism do you use?
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What authorisation mechanism do you use?
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Deferred to scheduler implementation
Does service interaction need to be encrypted?
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Any provided by GT 4 Security (identity, gridmap, self,
CAS, callout, custom)
What accounting mechanism do you use?
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Any provided by GT 4 Security (WS-Security:
Username/Password, X.509 (w & w/o proxy certs) and
GSI Secure Conversation
No, but it can be
Delegation of rights:
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Delegation service
Exploiting the Service Architecture
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What features from your ‘plumbing’ do you
use in your service?
Logging
‹ Event notification
‹ Lifetime management
‹ Registry discovery/advertisement
‹ State inspection
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Service Activity
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Multiple interaction or single user?
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multiple
Throughput (1/per day or 100/per
second?)
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Depends/unknown
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Typical data volume moved in
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Typical data volume moved out
Service Failure
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Required Reliability
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Failure semantics?
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Required Persistence
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Positive ack (two phase commit)
Work never lost? - Yes
Required Availability
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Should always be available
Required Service Management
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Remote access to:
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Current state
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Job
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System