1. 12f.1 MPI and Grid Computing UNC-Wilmington, C. Ferner, 2008 Nov 4, 2008

2. 12f.2 MPICH-G2 MPICH is an implementation of the standard MPI MPICH-G is an implementation of MPI that uses the Globus Toolkit MPICH-G2 is a complete redesign and reimplementation of MPICH-G

3. 12f.3 MPICH-G2 MPICH-G2 hides heterogeneity by using the Globus Toolkit for –authentication –authorization –exectutable staing –process control –communication –redirection of standard input and output –remote file access

4. 12f.4 % grid-proxy-init % mpirun -np 6 myprog mpirun globusrun DUROC GRAM CondorforkSGE MDS GASS P0P1P2P3P4P5 Generates RSL Submits multiple jobs Authenticates, Coordinates Startup Initiates Job, Detects Termination Process Control

5. 12f.5 RSL mpirun will generate the RSL or one can create/provide the RSL This is RSL version 1 (not XML)‏ + ( &(resourceManagerContact="m1.utech.edu") (count=10)‏ (jobtype=mpi)‏ (label="subjob 0")‏ (environment=(GLOBUS_DUROC_SUBJOB_INDEX 0))‏ (directory=/homes/users/smith)‏ (executable=/homes/users/smith/myapp)‏ )‏ ( &(resourceManagerContact="m2.utech.edu") (count=10)‏ (label="subjob 1")‏ (environment=(GLOBUS_DUROC_SUBJOB_INDEX 1))‏ (directory=/homes/users/smith)‏ (executable=/homes/users/smith/myapp)‏ )‏ ( &(resourceManagerContact="c1.nlab.gov") (count=10)‏ (jobtype=mpi)‏ (label="subjob 2")‏ (environment=(GLOBUS_DUROC_SUBJOB_INDEX 2))‏ (directory=/users/smith)‏ (executable=/users/smith/myapp)‏ )‏

6. 12f.6 Topology Early implementations of MPI's collective communication operations assumed all processes were equidistant from on another. This assumption is unlikely in a Grid environment 01 23 Shared-Memory 45 67 Cluster 1 89 1011 Cluster 2 Site ASite B

7. 12f.7 Topology Use the concept of Communicators, MPICH-G2 collective communication operations are topology-aware. It uses the concept of “levels” and “colors”