WSMP: Watson Sparse Matrix Package (Version 8.10.15)

What's New and What's Coming Up

• Two new massively parallel platforms, Blue Gene P and Cray XT4 are now supported.
• New symmetric factorization algorithms have been introduced that reduce memory use in multithreaded mode.
• The symmetric indefinite solver with diagonal pivoting has been improved significantly. It is faster and can now handle singular matrices.
• All symmetric solvers in WSMP can now handle more than one matrices simultaneously.
• Software available from alphaWorks for AIX, Linux, and SunOS.
• If you need WSMP and PWSMP libraries for any other platform, please send e-mail to discuss the possibility.
• 64-bit multithreaded libraries supporting 8-byte integers are available for all platforms. Please send e-mail if you need one and do not find it in the download from alphaWorks.

Software Documentation

• WSMP User Guide Part I -- Symmetric Systems
• WSMP User Guide Part II -- General Systems

Related Papers and Reports

• Comparison of iterative solvers for SPD systems
• Comparison of general solvers
• Unsymmetric solver algorithms
• Shared- and distributed-memory parallel general solver
• Symmetric solver details
• Parallel symmetric algorithm
• Raw results from an experimental comparison of WSMP, MUMPS, and SuperLU_DIST for general matrices on up to 32 IBM Power3 450 MHz CPUs.

Miscellaneous

• C++ wrapper for the message passing library, thanks to Rich Lee at Stanford Linear Accelerator Center.
• Link for downloading fast BLAS libraries to speed up WSMP on certain platforms.
• Link to WSMP's alphaWorks page.

Known Bugs and Issues

• On AIX, setting the environment variable RT_GRQ to ON if smt_threads are enabled can result in performance degradation. RT_GRQ must be set to OFF if smt_threads are enabled and ON if smt_threads are disabled.
• The new serial/multithreaded symmetric solvers are more memory efficient than the older ones, but may be slower for matrices whose factors are fairly sparse. If you notice a slowdown in your application and if memory is not a constraint, you may switch to the older solvers by setting IPARM(31) = 5 or 6.
• The calling sequences of some routines of the simple interface have changed. Please refer to the section titled "Recent Changes and Other Important Notes" in the User Guide for more details.
• The AIX libraries are provided both with and without BLAS. For large 3-D problems, ESSL BLAS is much faster and should be linked with the WSMP libraries built without BLAS.
• Running WSMP in 64-bit mode with multiple threads on certain Linux distributions can result in severe memory fragmentation or memory leaks. This is due to a bug in the glibc malloc library, and is not a WSMP bug. If you encounter this problem, then please download the file tcml.tar.gz and follow the instructions in this README file to bypass glibc malloc and use Google's TCmalloc library instead. This should fix the problem.
• On Linux, the environment variables MALLOC_TRIM_THRESHOLD_ and MALLOC_MMAP_MAX_ must be set to -1 and 0, respectively.
• On AIX, the environment variables SPINLOOPTIME and YIELDLOOPTIME must be set to 200, AIXTHREAD_COND_DEBUG and AIXTHREAD_MUTEX_DEBUG must be set to OFF.
• The Linux versions of the distributed-memory parallel unsymmetric solver can use only one thread per process because the MPICH/MPI implementations on these systems are not thread-safe. Therefore, the WSETMAXTHRDS routine must be used to set the number of threads to 1.
• HP-UX on PA-RISC, Tru64 on HP/Compaq/DEC Alpha, and SunOS on Opteron processors are not supported any more; older versions of the software are still available at alphaWorks.

Example Programs

• memchk.c (to check the amount of stack and heap space available to you)
• triplet2cs.c (to convert a sparse matrix from triplet to CSC/CSR format)
• wgsmp_ex1.f, wgsmp_ex2.f (small tests for the unsymmetric solver)
• wssmp_ex1.f, wssmp_ex2.f (small tests for the symmetric solver)
• pwssmp_ex1.f, pwssmp_ex2.f, pwssmp_ex3.f (tests for message-passing symmetric solver)
• pwgsmp_ex1.f (test for the distributed-memory parallel unsymmetric solver)
• zgsmp_ex1.f (test for the complex unsymmetric interface)
• zssmp_ex1.f, pzssmp_ex1.f, pzssmp_ex2.f, pzssmp_ex3.f (tests for serial and parallel symmetric complex interface)

Other Links

• Anshul Gupta's Home Page