OpenMP/Benchmarks

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Revision as of 23:43, 23 July 2013 by HamishBowman (talk | contribs) (Neighborhood analysis)

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Neighborhood analysis

Performance using OpenMP and different compilers:

source|svn/sandbox/soeren/benchmarks/neighborhood_openmp/

Best to run it 4 times for each case, discard the first and average the next 3.

Example usage:

 unset OMP_NUM_THREADS
 time ./neighbor 5000 5000 23
 
 export OMP_NUM_THREADS=1
 time ./neighbor 5000 5000 23
 
 ...
 
 export OMP_NUM_THREADS=6
 time ./neighbor 5000 5000 23

Test setup: 5000x5000 array with a window size of 23x23 cells

results table:

CPU Available cores OMP NUM THREADS Time "real" Time "user" Time "sys" Compiler Compiler version Compiler flags OS System RAM Data sum Data mean
AMD Phenom II X6 1090T 6 1 134.70s 137.78s 0.89s gcc 4.4.5 -O0 Debian GNU/Linux 6.0.7 (squeeze) 8.0 gb
AMD Phenom II X6 1090T 6 2 65.73s 129.46s 0.89s gcc 4.4.5 -O0 Debian GNU/Linux 6.0.7 (squeeze) 8.0 gb
AMD Phenom II X6 1090T 6 4 37.26s 145.96s 0.52s gcc 4.4.5 -O0 Debian GNU/Linux 6.0.7 (squeeze) 8.0 gb
AMD Phenom II X6 1090T 6 6 25.17s 147.70s 0.49s gcc 4.4.5 -O0 Debian GNU/Linux 6.0.7 (squeeze) 8.0 gb