On Tue, 2008-02-12 at 19:04 -0200, Matias Alberto Gavinowich wrote:
> Hi,
> 
> Thanks for the answers I received.
> 
> I see how the schema your mention would work, although I am not sure
> how I would implement it. I envision a web service that could receive
> a listener as a parameter and return some kind of id to retrieve it,
> or perhaps something based on the whole collections of jobs for a
> user, which would resemble your example more closely. I guess - I am
> not sure - that this would imply making the listener also
> serializable, and using a stateful web service instead of a plainly
> standard one, so it would have to live in the GT4 container. Is what I
> described you meant?

When I said "service" I didn't necessarily mean "newtwork service". It
can be a static hashtable.

> 
> As for GT2 vs GT4, I am a bit lost with the GramJob classes, I am
> reading mainly the javadoc at
> http://www.cogkit.org/release/4_1_4/api/jglobus/index.html and also
> some others I found in other sites like globus, but I am not really
> sure which are pre-WS (GT2) and which are WS (GT4).

Jglobus only deals with pre-WS gram. For the ws-gram GramJob see
http://www-unix.globus.org/api/javadoc-4.0/globus_wsrf_gram_client_java/.

> 
> I put some further thought into the problem and I think I would run
> into some more problems with TaskGraphs (from Abstractions). I hoped I
> could do a kind of full monitoring of the status so that if a user
> submitted a TaskGraph I would be able to tell which task in the
> taskgraph was executing and the progress corresponding to that
> specific task, and present this to the user in the portal. Perhaps I
> trying to squeeze more out of it than I should? It would be nice to be
> able to submit complex (composed) tasks to the grid and provide that
> kind of granular monitoring, so I would be able to tell the user 'Your
> job has staged the input files, run, and is now staging the output
> files back to your directory, and this last step is complete at 65%'.

I'd say start with the simple things first. They seem to have a tendency
to be more complicated than they appear.

Mihael

> 
> By the way, thanks for letting me know I should not be using the gt2
> fault tolerant provider, you saved me some time trying to reedit my
> experiments with it.
> 
> Regards,
> 
> Matt
> 
> 
> On Feb 12, 2008 4:10 PM, Mihael Hategan <[EMAIL PROTECTED]> wrote:
> > So I think your best bet is to have some background services in the
> > portal that you attach or detach to a portal session. In other words,
> > you can have the CoG objects alive even when a user logs out. So
> > basically a session of your own that is only loosely connected to the
> > portal session. This way you get the benefits of both worlds. For
> > example:
> >
> > -login happens
> > register(username, statefulObject);
> > -logout happens
> > -stuff happens in the background
> > -login happens
> > statefulObject = retrieve(username)
> > ...
> >
> > Some more specific answers inline.
> >
> >
> > On Tue, 2008-02-12 at 14:38 -0200, Matias Alberto Gavinowich wrote:
> > > Hi,
> > >
> > > I am writing to see if anyone can give me any pointers on monitoring
> > > file transfer and job submission tasks on the Grid. What I would like
> > > to do is to be able to present detailed information such as status of
> > > the job (ideally even if sent to a PBS batch system) and progress
> > > (e.g. in percentage) of a file transfer, even if the user logs out and
> > > then back in into the portal (so registering a listener in the session
> > > is not enough in my case). The monitoring that the batch job
> > > submission portlet in OGCE provides is pretty much what I want for the
> > > job case.
> > >
> > > Now the issue I am having with this: I am trying to apply the Java CoG
> > > Kit abstractions. That is, I have studied the code for the batch job
> > > submission portlet and I know it employs the GramJob class in the
> > > (jGlobus?) part of the CoG API. I haven't tried to do this for file
> > > transfers so I also don't know how it would be done in that case.
> > >
> > > Nevertheless, using the abstractions I was only able to register a
> > > listener in the session, which constrained me mainly to synchronous or
> > > almost synchronous executions. What I like about the abstractions is
> > > their simplicity and implementation of object oriented concepts. If I
> > > used e.g. the GramJob class, then as far as I know I need to build the
> > > rsl.
> > >
> > > These are therefore the main items I am in doubt about:
> > >
> > > Is it possible to use the CoG Abstractions for the purpose I
> > > described? Or at least is there a way to get the native job handle
> > > from the abstractions and build a GramJob object just for the purpose
> > > of monitoring the task, that is, combine both techniques? The only
> > > handle I could get my hands on was a urn:cog handle that I didn't know
> > > what to use for.
> >
> > The internals of the implementation are not much exposed by the
> > abstractions API. So you'd probably have to use the implementation APIs
> > directly.
> >
> > >
> > > I am not sure the extent up to which GramJob works with GT4 (WS-based)
> > > execution,
> >
> > It doesn't. But GT4 has a GramJob of its own. Though fairly different
> > from the pre-ws gram one.
> >
> > >  I have seen that a GramJobPreWS object is also used in the
> > > portlet I studied, can I get this GramJob class to work with any
> > > provider (at least any globus provider, namely gt2 and gt4)?
> > >
> > > How would this be done for file transfers?
> >
> > Same principles apply.
> >
> > >
> > > I would greatly appreciate your comments on these topics. If there's a
> > > way to combine approaches so as to get the advantages of using the
> > > abstractions, that would be great. If anyone has further examples on
> > > how to achieve such monitoring without the abstractions, that would
> > > also be helpful. Even examples on monitoring using the abstractions
> > > only in the same session - though I would really like to be able to
> > > span sessions - would come in handy.
> > >
> > > I'd like to add I once tried to do this by using the gt2 fault
> > > tolerant provider and trying to checkpoint and reconnect to tasks, but
> > > I was never able to get this to work, even from the command line.
> >
> > Hmm. I just removed that one from SVN. Hasn't been maintained in a while
> > and you're the only person I heard of to have tried to use it.
> >
> > Mihael
> >
> >
> > >
> > > Thank you a lot for your help,
> > >
> > > Matt
> > >
> >
> >
> 

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