Implementing Parallel Codes
                       February 15, 2006





Presented by the
ITC Research Computing Support Group                
Kathy Gerber, Ed Hall, Katherine Holcomb, Nancy Kechner, Tim F. Jost Tolson

ITC Research Computing Support
Implementing Parallel Codes

MPI=Message-Passing Interface

MPI is a Library

Messages

MPI Datatype

MPI Datatype

Collective Communications

Global Reduction Operations

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Point-to-Point Communications

Slide 17

MPI Send-Receive

Blocking Send-Recv and Safety

Another Unsafe Pattern

EXAMPLE 2: Jacobi Iteration

Sample Parallelization Strategy

Exchange Edge Data at Each Iteration

One Solution

Slide 25

Another Solution

Nonblocking Sends and Receives

EXERCISE

Exercise [cont.]

HOMEWORK

MPI References

Web Resources

Parallelization Without MPI
Parallel Libraries

ScaLAPACK

IMSL

On the Horizon

Some Useful Information