Response #1: 2005-09-14

General

1. Is dense linear algebra a performance bottleneck in your applications?
Yes

2. How often do your applications use the arithmetic precisions listed below:

3. What dense matrix sizes are most important or time-consuming for your application?
10,000s X 10,000s

4. Does your application come close to, or run out of memory on important problems?
Yes

5. Number of processors used for your application:

6. Which architectures do you use or intend to use in the next three years?
Multi-core-thread, Distributed-shared-memory, Distributed-memory, Hybrid-shared

7. Do you use any other sequential or parallel dense linear algebra packages other than LAPACK or ScaLAPACK?
PLAPACK

8. Please rank how the following features would be useful to your current or planned applications?

9. Do your applications solve linear algebra problems of the type?
Linear positive definite systems, General linear systems, Symmetric eigenvalue, SVDs

LAPACK Usage

1. Do you use LAPACK (or a vendor version of LAPACK )?
Yes

4. If you use LAPACK, do you use a vendors version or one obtained directly from Netlib?
Netlib

6. Do your applications make direct LAPACK calls?
Yes

7. Do your applications use libraries which depend on LAPACK?
Yes

8. Do your applications use a higher-level interface to LAPACK?
No

10. Is the LAPACK procedure interface a barrier to more extensive use?
No

11. From which languages do you call LAPACK routines?
Fortran 90/95, Fortran 2003

14. If you have installed LAPACK yourself, how could the installation process be improved?
see Scalapack comments below.

15. How frequently do you refer to the LAPACK Users Guide?
Frequently

16. What information in the LAPACK guide is hard to find or is missing, if any?
See Scalapack comments below.

ScaLAPACK Usage

1. Do you use ScaLAPACK (or a vendor version of ScaLAPACK )?
Yes

4. If you use ScaLAPACK, do you use a vendors version or one obtained directly from Netlib?
Netlib

6. Do your applications make direct ScaLAPACK calls?
Yes

7. Do your applications use libraries which depend on ScaLAPACK?
No

8. Do your applications use a higher-level interface to ScaLAPACK?
No

10. Is the ScaLAPACK procedure interface a barrier to more extensive use?
No

11. From which languages do you call ScaLAPACK routines?
Fortran 77

12. Please describe any tools or helper functions that you frequently implement to assist your applications in using ScaLAPACK?
PBLAS redistribution routines: pdelset, pdelget, indxl2g etc.

13. How could the ScaLAPACK interface be improved to feel more natural to your application and implementation language?
Get rid of the dependance on BLACS. BLACS contexts in particular are unwieldy and difficult to use and understand.

14. If you have installed ScaLAPACK yourself, how could the installation process be improved?
Clearer options for compiling Single/Double/Real/Complex libraries only. Better and clearer validation routines.

15. How frequently do you refer to the ScaLAPACK Users Guide?
Very Frequently

16. What information in the ScaLAPACK guide is hard to find or is missing, if any?
More information on the underlying algorithms used in the various routines would be useful.

Targeted Environment Specifics

1. Under which operating system environments do your applications run?
AIX, Linux

3. If your applications run in a distributed-memory environment, which styles of parallelism do they employ?
Message passing

Additional Information