Sysbench CPU test: gcc vs. cc

Yet another test with Sysbench I did some time ago. This time please notice how big the difference is on both platform when Sysbench is compiled using Sun's Studio 12 (cc) compiler vs. gcc. I guess that tweaking parameters in gcc could get it closer...
Anyway, here is a graph.



Please notice that Niagara-2 cc results are for all N values. With N=32,64,128 total time is about 0.2-0.3s so you can't see it on graph.

In previous test (Sysbench's Memory test - there's basicaly no difference between gcc and cc).

Details:
./sysbench --test=cpu --cpu-max-prime=2000 --num-threads=N run

v440 4x1GHz USIIIi
Niagara-2 8-core 1.4GHz
gcc -O2 or -O3 or defaults from configure - the same results
cc -fast