[jsdl-wg] a couple of questions

[Ariel Oleksiak]

Hi All,

That's me again. Please find another portion of questions and comments
concerning the latest versions of JSDL specification and schema. These
issues arisen mainly when we were trying to map JSDL to other job
description languages.

1. In one of my previous emails I asked about specification of a directory
in the DataStaging element and I got the answer that this is possible.
Therefore, in my opinion, what we need is the attribute which distinguishes
between regular file and a directory. I think that a scheduler may often
need this knowledge to perform data staging (e.g. it may have to know
whether a given logical name is the name of file or directory in order to
call appropriate methods of a data management system).

2. I guess the NetworkBandwidth element defines the maximal bandwidth of the
networking interface for a given resource. Such a metric is rather useless
in a resource selection process because indeed only the actual bandwith
between two nodes is really important. So didn't you think about the element
defining bandwith between two nodes, e.g. containing an attribute to specify
the second node?

3. Some time ago we discussed defining of software dependencies, e.g.
necessary libraries etc. and I sent some simple use-cases. I do not see this
element in the spec. Have you come to the conclusion that this is not
general enough?

4. What is the meaning of the "other" value in the list of OSs, processor
architectures etc.? Does it mean that (i) a scheduler has to select
resources limited to those having OS OTHER than the remaining OSs from the
list or (ii) that a certain OS, not included in the list, is required and
its exact name is included in an additional element (which one?). In my
opinion the latter is more rational (actually I don't see any use case for
the former) but, if so, how this OS should be specified - using the
Description element, extension?

5. The next question is related to the semantics of resource requirements in
JSDL. Are resource requirements limited to required amounts of resources
available for user's application (e.g. free CPUs, free memory etc.) in a
given point of time or they also enable a user to specify required total
amounts of resources (e.g. total number of CPUs, total virtual memory etc.)?
Of course the former (dynamic) values are much more important during
resource selection, however, information about some of them may not be
available in all grid environments. Anyway this distinction must be clearly
defined.

6. I see that units and operators attributes disappeared from the schema. I
understand that operators can be expressed using RangeValueType and units
are defined in the specification now?

7. It is not clear for me what is the difference between Range elements and
Upper/LowerBoundedRange in the RangeValueType. Sorry if it has been already
explained elsewhere.

8. I cannot find a way to specify a type of application in terms of its
architecture (single, mpi etc.). I suppose that you consider it as too
specific and as a possible extension or maybe this is an oversight?

Thanks,
Ariel