[ogsa-bes-bof] RE: [ogsa-wg] Perhaps useful input to BES discussion

Wed May 25 11:58:35 CDT 2005

Hi Ian,

We've discuss your input on Sunday (at OGSA-BES meeting) and Monday
(at OGSA-WG meeting). The attached is an understanding of the attendees.

Each box corresponds to EMS service and each dotted line shows coverage
of OGSA-BES WG's charter, OGSA-RSS WG's (initial) charter, and GRAM
interface.

Some comments;
- We think MJFS corresponds to container instead of Job Manager.
- MJFS and others cover most of "container" interface but not all.
For example, BES-WG will define check-pointing interface which
is not supported by GRAM.
- GRAM covers "job" interface, which is out of BES-WG's scope.

Meeting minutes will be available shortly and you can find more detail
by the minutes.

Thanks,
----
Hiro Kishimoto

-----Original Message-----
From: Ian Foster [mailto:foster at mcs.anl.gov] 
Sent: Monday, May 23, 2005 11:20 PM
To: Hiro Kishimoto; 'ogsa-wg'; OGSA-BES-bof at ggf.org
Subject: RE: [ogsa-wg] Perhaps useful input to BES discussion

Hiro:

The "BES is for container not job manager" argument doesn't make sense to me.
The question of where you are permitted to direct operations for purposes of
monitoring and control--to container, job, or both--is orthogonal to the
question of what operations need to be supported.

The draft BES document defines "check status" and "terminate" operations, which
are certainly required. However, more are needed, e.g.:

* soft-state lifetime management, to avoid orphan jobs

* subscribe-on-status-change operations, to avoid repeated polling.

Simply saying "we're not going to consider those because they are defined in
WSRF" makes no sense to me. WSRF also defines "check status" and "terminate"
operations, but you're not ignoring those.

Another generic issue that is not addressed in the BES document is how you model
the state associated with the factory and an individual job. Regardless of how
you choose to provide access to that state, via standardized WSRF operations or
some custom operations, a schema needs to be defined implicitly or explicitly,
and this must surely encompass more than just "job status." E.g., see below for
those defined in GT4 GRAM.

With respect to your questions below:

#1: Yes, in my view.

#2: I certainly think you need to consider and address these issues together.

Ian.

Job modeling, from
http://www.globus.org/toolkit/docs/4.0/execution/wsgram/WS_GRAM_Public_Interface
s.html#id2844424
2.3.2. Managed Job Port Type
. serviceLevelAgreement: A wrapper around fields containing the single-job and
multi-job descriptions or RSLs. Only one of these sub-fields shall have a
non-null value. 
. state: The current state of the job. 
. fault: The fault (if generated) indicating the reason for failure of the job
to complete. 
. localUserId: The job owner's local user account name. 
. userSubject: The GSI certificate DN of the job owner. 
. holding: Indicates whether a hold has been placed on this job. 

2.3.3. Managed Executable Job Port Type
. stdoutURL: A GridFTP URL to the file generated by the job which contains the
stdout. 
. stderrURL: A GridFTP URL to the file generated by the job which contains the
stderr. 
. credentialPath: The path (relative to the job process) to the file containing
the user proxy used by the job to authenticate out to other services. 
. exitCode: The exit code generated by the job process. 

2.3.4. Managed Multi-Job Port Type
. subJobEndpoint: A set of endpoint references to the sub-jobs created by this
multi-job. 

2.3.5. Faults
. FaultType: This is the base fault for runtime errors that occur while managing
a job. It extends the OGSI FaultType. 
. CredentialSerializationFaultType: This fault indicates that the managed job
service was unable to serialize or deserialize a delegated credential. 
. InsufficientCredentialsFaultType: This fault indicates that the managed job
service was unable to perform some action on behalf of the owner of the job
submission because the owner has delegated insufficient credentials. 
. InternalFaultType: This fault indicates that an internal operation failed. 
. InvalidCredentialsFaultType: This fault indicates that the managed job service
was unable to use a delegated credential. 
. ServiceLevelAgreementFaultType: Fault for runtime errors which are directly
related to a particular part of the ServiceLevelAgreement document passed to the
createService method. This fault type contains the fragment of the
ServiceLevelAgreement related to the fault as one of its elements. 
. ExecutionFailedFaultType: This fault indicates that the Managed Job service
was unable to begin the execution of the job. 
. FilePermissionsFaultType: This fault indicates that the ManagedJob service
does not have permissions to access a file referenced in the
ServiceLevelAgreement. 
. InvalidPathFaultType: This fault indicates that a file or directory path
referenced in the ServiceLevelAgreement contains an invalid path. 
. StagingFaultType: This fault indicates that part of the file staging
requirements of the ServiceLevelAgreement could not be completed. 
. UnsupportedFeatureFaultType: This fault indicates that an error occurred
because the RSL depended on a feature not implemented by a particular GRAM
scheduler. 

At 04:53 PM 5/23/2005 +0900, Hiro Kishimoto wrote:

Hi Ian,

Thank you for your excellent and thoughtful document!

Yes, we have had a very related discussion at the meeting yesterday.
We've discussed that BES defines subset of your 8 operation (1, 2, 7,
and 8). Please remember BES is for Container not for Job Manager.

The climate of the meeting is "container (factory) interface only, no 
job interface." And the reason is operation 2 and 7 are already specified
in WSRF.

However, I still wondering the following two issues;

(1) Even though interface is already defined in the WSRF, don't we need
to define domain-specific semantics and behavior (e.g. job destroy means
soft kill).

(2) Given that Job Manager defines Job interface explained in Ian's
document, combination of Job Manager and Container introduces
unexpected complexity in EMS architecture? (Job itself has its own
interface in the context of Job Manager but has no interface in the
context of container).

Your thoughts?
----
Hiro Kishimoto

-----Original Message-----
From: owner-ogsa-wg at ggf.org [mailto:owner-ogsa-wg at ggf.org] On Behalf Of Ian
Foster
Sent: Sunday, May 22, 2005 7:37 AM
To: ogsa-wg; OGSA-BES-bof at ggf.org
Subject: [ogsa-wg] Perhaps useful input to BES discussion

Dear All:

I am sending this draft document in case it is relevant to the OGSA-WG and/or
BES discussions.

In this document, I use a simple example (a skeleton execution service) to
compare and contrast four approaches to representing state, namely WSRF,
WS-Transfer, REST, and "state id." 

I haven't sent this earlier because I'd hoped to integrate numerous comments
that I've received from Savas and others. I hope to do so in the next week or
two, but perhaps this draft is still of interest.

Regards -- Ian.

_______________________________________________________________
Ian Foster                    www.mcs.anl.gov/~foster
Math & Computer Science Div.  Dept of Computer Science
Argonne National Laboratory   The University of Chicago    
Argonne, IL 60439, U.S.A.     Chicago, IL 60637, U.S.A.
Tel: 630 252 4619             Fax: 630 252 1997
        Globus Alliance, www.globus.org
_______________________________________________________________
Ian Foster                    www.mcs.anl.gov/~foster
Math & Computer Science Div.  Dept of Computer Science
Argonne National Laboratory   The University of Chicago    
Argonne, IL 60439, U.S.A.     Chicago, IL 60637, U.S.A.
Tel: 630 252 4619             Fax: 630 252 1997
        Globus Alliance, www.globus.org
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