$ NUM_THREADS=1  ./rtoa-pgatram-allinone2d t1.txt t1.txt t1.txt t1.txt | cksum
do_it_all time    :    0.489 secs
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$ NUM_THREADS=4  ./rtoa-pgatram-allinone2d t1.txt t1.txt t1.txt t1.txt | cksum
do_it_all time    :    0.144 secs
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$ NUM_THREADS=8  ./rtoa-pgatram-allinone2d t1.txt t1.txt t1.txt t1.txt | cksum
do_it_all time    :    0.075 secs
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$ NUM_THREADS=16 ./rtoa-pgatram-allinone2d t1.txt t1.txt t1.txt t1.txt | cksum
do_it_all time    :    0.048 secs
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