I compiled a benchmark program by pgcc 6.0.5 and pgcc 5.2.4
on a 2 AMD opteron 250 CUP machine and run it.
% pgcc -fastsse -Mconcur -DLARGE himenombmtxps.c
The measure by the benchmark program shows that it runs at 1364 Mflops for pgcc 6.0.5
while at 1653 Mfops for pgcc 5.2.4, about 20% faster. If only use single CPU
% pgcc -fastsse -DLARGE himenombmtxps.c
both run at about 1160Mflops with several percent difference.
I tested several compiler options described in Users’ Guide but I could not
run the benchmark test compiled by pgcc 6.0.5 as fast as by 5.2.4.
Do you know why this benchmark program compiled -Mconcur by pgcc 6.0.6
is signigicanly slowe than compiled by pgcc 5.2.4?