Release 11.4 (January 2016) of GEMPACK

Release 11.4 includes fixes for several smaller bugs detected during the last year, and it offers several speed-ups, both at compile time (LTG) and at runtime.

• Much faster compiling: Some users reported that compile times with Source-code GEMPACK 11.3 (the previous release) and Intel Fortran 15 were very slow when compared to compile times with Intel Fortran 14. For Source-code GEMPACK 11.4 the LTG or compile time has been speeded up by a factor of 3 for GFortran and a factor of 2 for Intel Fortran compilers (running on a quad core Intel CPU). This is achieved by using multiple CPU cores in parallel and in the case of GFortran by also using improved compiler options.
• Much faster GEMSIM: We noticed that Source-code GEMPACK users of Intel Fortran 15 and 16 suffered from slow GEMSIM runtimes. We fixed this issue, and as a side-effect have speeded up GEMSIM by 30%-70%, depending on the model used, even when built with other compilers.
• For GFortran TABLO-generated EXEs: Improved compiler options have reduced runtimes by up to 30%, particularly for 64-bit exes.
• Faster LU decomposition: For the first time, we have introduced some thread-level parallelism. For now, this only affects the LU phase, typically reducing LU times by 20%. The effect is most noticeable for models like GTAP and TERM where the LU phase accounts for half or more of total runtime. We plan to introduce more thread-level parallelism, reducing non-LU times, in later releases.
• Source-code GEMPACK 11.4 supports the Intel Fortran compiler versions 13 to 16. The current release is 16; the simplest and cheapest way to obtain it is as part of the package Intel Parallel Studio XE Composer Edition for Fortran Windows while Uni students may qualify for free use.

The table below compares GEMPACK 11.4 compile times (LTG) and model runtimes with those for the previous 11.3 version. We list results for GTAP (which is LU-bound) and MMRF (where non-LU operations dominate runtime). Results are shown for the Intel, GFortran and Lahey/Fujitsu compilers, in each of 32-bit and 64-bit versions where supported. Runtimes are reported for both GEMSIM and Tablo-generated exes.

GEMPACK 11.4 and 11.3 compile times (LTG) and runtimes in seconds

Tests were run on a desktop PC running Windows 7 64-bit with an (quad-core) Intel i7-4770 CPU, 32 GB memory and 512 GB SSD hard drive. Compilers were: GFortran 4.8.1, Intel Fortran 14.0 and Lahey/Fujitsu Fortran 7.2 professional.

A more comprehensive compiler comparison is available on our supported Fortran compilers page.

The table shows striking reductions in LTG times, and useful runtime speedups for LU bound models represented here by the GTAP model. Also noteworthy, free GFortran is marginally faster than Intel Fortran for the Tablo-generated executable program implementation of MMRF.

Availability

Release 11.4 will be supplied to all new GEMPACK purchasers. Current subscribers to the annual payment scheme for the source-code version of GEMPACK are advised to download a free upgrade -- they should email sales@gempack.com (specifying their licence number) for further details.

Advice to GFortran source-code users

Note that GEMPACK 11.4 or later requires GFortran version 4.8.1 (it actually fails to compile with the older GFortran 4.5). If upgrading to GFortran version 4.8.1, first uninstall the older GFortran. [In Control Panel "Programs and Features" uninstall "MinGW-w64 version 1.0 GCC 4.5.4 prerelease (GEMPACK compatible)". More information.]

Advice to Intel Fortran source-code users

EXE files produced by GEMPACK 11.4 and the Intel compiler need to have access to a file called libiomp5md.dll. Normally access is guaranteed, since this file comes with both GEMPACK 11.4 and Intel Fortran. However, if you use GEMPACK 11.4 (or later) with Intel Fortran and intend to distribute TABLO-generated EXE files (for example, in RunDynam archives or in RunGTAP version zips) to other people who might not have installed Intel Fortran or GEMPACK 11.4, you should be aware of the missing DLL problem.

See also:
Improvements for GEMPACK Release 11.3 (Jun 2014, January 2015)
Improvements for GEMPACK Release 11.2 (May 2013)
Improvements for GEMPACK Release 11.1 (May 2012)
New features of GEMPACK Release 11.0 (October 2011)
Improvements for GEMPACK Release 10.0-001 (April 2009)
All GEMPACK release notes
Different versions of GEMPACK