1. P-GRADE overview and introduction: workflows & parameter sweeps (Advanced features)
Gergely Sipos
MTA SZTAKI

2. Parameter Sweep applications
Typical usage of the Grid is that the same application is executed with many different parameters
P-GRADE portal from release 2.5 supports this functionality
The next part of the lecture shows how parameter sweep (PS) applications are supported by P-GRADE portal

3. Scaling up a workflow to a parameter study with P-GRADE
Complete workflow
Input file set in an LFC directory (e.g. lfc:/grid/gilda/sipos/myinputs)
Output file set in an LFC directory (e.g. lfc:/grid/gilda/sipos/myoutputs)

4. Turning a WF into a parameter study
By turning at least one of the open input ports into a “PS Input port” the WF is turned into a Parameter Study WF

5. PS Input Port of Simple PS
Remote file Directory instead of FILE reference

6. Simple PS Activity 2: placement of result
Menu item
PS Properties is available in the Workflow menu
Properties of the VO File Catalog
The Output directory will contain the ZIP-ped result files of the Workflow executions
One SE of the VO – Choose a reliable one!

7. Executing PS workflows
PS Details for parameter sweep workflow applications

8. Workflow Manager List PS Details view showing eWF-s
Status of complete application
Statistics of workflows generated from the application
Workflow list shows the state of the generated Workflows.

9. Advanced PS WFs in P-GRADE Portal

10. Advanced parameter studies
Generator component(s)
Initial input data
Generate or cut input into smaller pieces
Complete workflow
Collector component(s)
Aggregate result
Files in an LFC directory (e.g. /grid/gilda/sipos/myinputs)
Files in an LFC directory (e.g. /grid/gilda/sipos/myoutputs)

11. Concept of advanced parameter study workflows
GEN
Generator part generates the input parameter space
SEQ
SEQ
SEQ
SEQ
Parameter study part
COLL
Collector part evaluates and integrates the results

12. The generic PS workflow application
First phase: executing the generators
Second phase: executing the “real” processor jobs for each input file combination
Third phase: executing the collectors

13. Detailed view of a PS workflow
Generator job(s)
Overall statistics of workflow instances
Workflow instances
Collector job(s)

14. PS practical