[Gems-users] Instructions executed

[Vivek Venkatesan <vvenkate@xxxxxxxxxxx>]

Hello All,

I'm having trouble making an  accurate comparison between two coherence 
models both based on MOESI_CMP_directory with Ruby. I am using a 16-core 
CMP and my initial approach was to run the same benchmark with the two 
models for a specific number of instructions (c 50000000) and compare 
the total ruby cycles elapsed. This didn't work because the 2 runs 
resulted in a different number of total instructions executed.
Another method I tried was to have a magic instruction at the beginning 
and end of the benchmark so that I can track the total ruby cycles taken 
to complete the entire benchmark. Then again, the total instructions 
executed differed (which did not make sense to me at all, especially 
since both start from the same checkpoint).
So how would I go about making a fair comparison of the two models? Is 
there any way you can make simics execute a certain number of total 
instructions or make ruby execute a certain number of total cycles?
Thanks much.

-Vivek