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This is the Berkeley Unified Parallel C (UPC) implementation of the NAS Parallel Benchmark FT. The transpose communication is implemented using both blocking functions (upc_memget) and nonblocking functions (upc_memput_nb). The default is nonblocking functions, which is defined in UPC description 3.1. If nonblocking functions are not supported on your system, it will switch to blocking functions automatically. Users are allowed to change the selection by modifying fft3d.uph file.

The NERSC-8 benchmark will run the Class DD16 (16 times bigger than NAS FT Class D) version of the UPC FT benchmark. Other Classes are supported in the released benchmark, but they are not required. 


UPC-FT tar file


The benchmark requires the FFTW version 3 library and a UPC compiler and runtime environment. 

  1. Set the path to your FFTW library in Make.fftw3
  2. Set the UPCC macro in Makefile to point to your upc compiler. It may be necessary to set a flag in UPCFLAGS to enable your compiler to build a UPC code.
  3. make

An executable file called ft-2d-upc.fftw3.DD16 will be generated.


There are two command line parameters (nx, ny) to represent the number of upc threads in the X and Y direction of a thread partition grid (nx * ny = total number of upc threads).  Users are allowed to change the values of nx and ny.

For example, on on the Cray at NERSC, the command line will be:
aprun -n 8192 ./ft-2d-upc.fftw3.DD16 64 128

where nx=64 and ny=128 (nx*ny = 8192)

Depending on your system type and configuration, it may be necessary to change the environment variable XT_SYMMETRIC_HEAP_SIZE to define the shared heap size.

Required Runs

The Class DD16 benchmark must be run using 8192 UPC threads.


The running results using 8192 upc threads for CLASS DD16 should be reported. In the benchmark spreadsheet, please report the following values reported by the program at the end of execution:

  1. Total running time
  2. Mflops/s
  3. Mflops/s/thread

Finally, please submit the output file along with the run script used and a description of the UPC compiler and runtime environment.