Hiro: So our email exchange has gone as follows: * You mentioned in email to OGSA-WG that a certain set of execution management commands have been defined as out of scope of BES because they relate to "job management" instead of "container management." * I said that this partitioning of function didn't make sense to me, for reasons that I listed. * You replied by re-iterating the position that the BES charter is defined to exclude what you term as "job management" functions. In my view, this reply doesn't address the issues that I raised, in that it just restates the position I was objecting to. I also note that the BES charter on gridforge.org notes that "The scope of the working group is on the definition of services for service instantiation and management. For example, using the OGSA V1 nomenclature, service containers and jobs." Thus I don't even see that this limitation is justified based on the charter. I'll stop raising the issue soon, but I do so one last time because I am concerned that a BES specification that is defined so narrowly is not going to be useful and thus will not gain broad acceptance. Regards, Ian. At 01:58 AM 5/26/2005 +0900, Hiro Kishimoto wrote:
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@mcs.anl.gov] Sent: Monday, May 23, 2005 11:20 PM To: Hiro Kishimoto; 'ogsa-wg'; OGSA-BES-bof@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_Inter... 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@ggf.org [mailto:owner-ogsa-wg@ggf.org] On Behalf Of Ian Foster Sent: Sunday, May 22, 2005 7:37 AM To: ogsa-wg; OGSA-BES-bof@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
_______________________________________________________________ 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