Update README.md

README.md

@@ -24,6 +24,9 @@ To generate 1GB of random data:
 $ ./random.x 1024 > randomdata
 
 ## Benchmark
+gcc version 4.8.5
+$ gcc -O3 -fopenmp random.c -o random.x  
+$ time ./random_pcg.x 32768 > /dev/null  
 
 | Processor                  |  random_hw.c [GB/s] | random_pcg.c [GB/s] |
 |----------------------------|---------------------|---------------------|