[drmaa-wg] Definition of "system"/discovery in getDrmSystem?

[Ed Baskerville]

Great, that clears everything up.

Thanks,
Ed

On Jun 6, 2006, at 11:53 PM, Peter Troeger wrote:

>> There's no clear definition for what a "DRM system" is in the 1.0
>> specification. I understand that it could be implementation-  
>> dependent,
>> but my assumption is that the generally accepted meaning  is  
>> "something
>> you can submit jobs to." On SGE, for example, then, it  seems then  
>> that
>> a system is the same as a cell. On Xgrid, they're  called, simply
>> enough, grids.
>
> Basically, this is something we already discussed and solved for the
> upcoming final 1.0 spec:
>
> http://forge.gridforum.org/sf/go/artf2822?nav=1
>
>> The SGE implementation seems to eliminate this concept  
>> altogether,  and
>> just require that SGE_ROOT and SGE_CELL be set, so when I call
>> getDrmaaImplementation and getDrmSystem (via Java) on SGE before
>> initialization, I get:
>>
>> getDrmaaImplementation: DRMAA 1.0 Java language binding 0.5 -- GE  
>> 6.0u7
>> getDrmSystem: GE 6.0u7
>>
>> SGE seems to displace the need for multiple "DRM systems" within   
>> DRMAA
>> by shifting the selection to the SGE_CELL environment variable.   
>> Is that
>> an accurate understanding?
>
> Citing myself from the tracker:
>
> -- snip
>
> "contact string" is a resource identifier that allows to contact a DRM
> system instance (e.g. Condor central manager machine at
> 123.123.123.123:4444)
> "DRM system" denotes a type of DRM software (e.g. Condor, SGE)
> "implementation" denotes a specific version of a DRM system (e.g.  
> Condor
> v6.6)
>
> -- snip
>
> So for SGE your impression seems to be right - but I am not the SGE  
> guy ;-)
>
>> I could certainly do something similar with Xgrid--let the user   
>> select
>> a default grid elsewhere--but, since Xgrid natively supports
>> Zeroconf/"Bonjour" discovery of grids, it would be nice to expose   
>> this
>> discovery in DRMAA.
>
> From a DRMAA perspective, it would be better to state all possible DRM
> instances (== XGrid grids == SGE Cells ???) as the result list of
> drmaa_get_contact() before drmaa_init().
>
>> So, the question is: does it make sense to expose Zeroconf grid
>> discovery via getDrmSystem?
>
> If you take the proposed definition above, getDrmSystem() is not the
> right one. You would use this with a DRMAA library supporting multiple
> DRM systems, like Condor and XGrid, in one implementation.
>
> Regards,
> Peter.
>