Scalapack blocksize dependency:
- Measurements:
- good agreement with Scalapack User Guide:
- generally use 64
- larger for large SMP machines
Scalapack processor grid dependency:
- Measurements:
- use 1xn grid
- Scalapack User's Guide:
- choose , one-dimensional for
Scalapack versus MLIB:
- Times:
- Efficiency:
- no Scalapack value for 1 cpu (needs 64bit version)
- no MLIB value for 16 cpus (cluster configuration)
- MLIB better for 1 and 2 cpus,
- Scalapack has better scalability
- Scalapack needs environment variable MPI_2BCOPY=1
(otherwise performance degradation to 25 %!)
Peter Junglas 6.3.2000