OMP results problem

[jpcoding]

results without openmp
./tools/sz3/sz3 -f -i $DATA/NYX_512x512x512/velocity_x.dat -3 512 512 512 -M REL 0.001 -o test.o -z test.z -a
compression ratio = 97.46
compression time = 5.325771
compressed data file = test.z
Min=-50416856, Max=31866786, range=82283642
Max absolute error = 8.2E+04
Max relative error = 0.001
Max pw relative error = 8.3E+05
PSNR = 68.309329, NRMSE= 0.0003841789261
normError = 366228371.376156, normErr_norm = 0.004903
acEff=0.999988
compression ratio = 97.458536
decompression time = 6.463747 seconds.
decompressed file = test.o

results with openmp on

./tools/sz3/sz3 -f -i $DATA/NYX_512x512x512/velocity_x.dat -3 512 512 512 -M REL 0.001 -o test.o -z test.z -a -c ../tools/sz3/sz3.config

compression ratio = 1.00
compression time = 0.200102
compressed data file = test.z
Min=-50416856, Max=31866786, range=82283642
Max absolute error = 8.2E+04
Max relative error = 0.001
Max pw relative error = 5.9E+05
PSNR = 67.269750, NRMSE= 0.0004330245281
normError = 412791688.771626, normErr_norm = 0.005526
acEff=0.999985
compression ratio = 0.999986
decompression time = 0.062369 seconds.
decompressed file = test.o

config file is attached here: sz3.config.txt