The SAGA Core API specification (GFD.90) is citing both the JSDL
specification (GFD.136) and the JSDL SPMD extension (GFD.115).
While SAGA is not directly using JSDL documents (XML documents), it
does reference the names of JSDL document elements, and their
semantics.
 
GFD.90 references the following SPMD Extension elements:
 
  - SPMDVariation
  - NumberOfProcesses
  - ProcessesPerHost
  - ThreadsPerProcess
 
It does not reference the SPMDApplication element, as that is
implicitely used for all SAGA job descriptions which use any of the
SPMD elements listed above.
 
Referencing the SPMD extension as defined in GFD.115 allows SAGA to
cover the majority of its SPMD related use cases.  In particular,
the dominating set of MPI use cases seems well covered.  Three
different SAGA implementations map the SAGA job description
(including its SPMD keys) to about ten different job submission
backends, where four of those backends actually support SPMD job
execution (gram, condor, lsf, sector/sphere).
 
A small number of SAGA use cases though is currently not covered by
either GFD.115, nor by GFD.90: those use cases require a more fine
grained specification of application layout, down to the assignment
of individual application threads to specific logical or physical
CPU cores.  We agree that these use cases are out of scope for the
JSDL working group, but would like to raise awareness of the
problem.
 
Summary: the SAGA Core API specification (GFD.90) successfully
references the JSDL SPMD extension (GFD.115), and we support the
advancement of GFD.155 to full OGF recommendation.