OpenMP/Benchmarks

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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

results table:

CPU Number of cores OMP NUM THREADS Time "real" Time "user" Time "sys" Compiler Compiler version Compiler flags OS System RAM
Intel i7 3770 4 real (8 w/ hyperthread) unset (all) example entry gcc 4.4.8 -O3 Ubuntu 12.04 8 gb