[Gems-users] GEMS on simics 4 - Parallelize gems - Un-stall simics for multiple cycles

[Andrea Bartolini <a.bartolini@xxxxxxxx>]

Dear experts,
I looked for informations on the mailing list about the possibility of run gems on simics 4. I did not found positive ones but is even true that are quite old. 
So I was wandering if anyone of you manage to run gems, mainly ruby, on  simics4. 

I noticed that the main changes are in some header files in simics 4.0, and I try to manually adapt it, but after 2 days still have compilation problem. 
I would like to use the simics 4 version since should have better performance, by meaning accelerator and native x86 executions. 
indeed I'm working with x86 simulation so I'm not using opal. 

I have other two questions:
1) If is possible to run gems with simics 4 and the accellerator, does anyone thought about parallelize gems and the eventqueue ? Ore someone of you already did it.
2) Since I'm using gems without opal, but only ruby + simics x86 simulator, I had a thought about how to improve the performance, and I would like to have a feedback from all you experts:
- I notice that the main slow down is due to the start and stop cycle-by-cycle of simics due to ruby module. I was wandering if it is possible to un-stall simics not cycle-by-cycle, but do it for bigger number of cycles. The number of cycles can be selected looking on the eventqueue and checking for the position of the next event posted. In this way you can speed-up the simulation by stop simics only when gems has something to do. Do you thinks this could work or there are drawbacks on doing this?

Thanks in advance,
Andrea Bartolini