Hi Andreas,

Thank you for your prompt reply and these days I am chewing on it. Your advices 
are very helpful and I am currently look into corresponding source code.
In the URL:http://reviews.gem5.org/r/1113/diff/?page=3, you did a lot of work 
and added distributed memory to gem5. Is the updated version of gem5 able to 
run software? Since the memory is distributed, how can I set the latencies and 
bandwidth for different pieces of memories? (Since closer memory provides lower 
latency)

Thank you in advance for your reading this and reply.
-Xiaobin

On Apr 3, 2013, at 9:36 AM, Andreas Hansson <[email protected]> wrote:

> Hi Xiaobin,
> 
> The short answer: Not out of the box.
> 
> The long answer:
> 
> You can definitely create the kind of system that you are describing in gem5, 
> with a "non-global" address map, but do not expect to easily run an OS on top 
> of it. The patch you describe lets you have multiple different memories, and 
> there is nothing forcing you to give all the CPUs the same memory map. 
> However, if you intend to actually run software, gem5 currently assumes you 
> run a single OS instance, and changing that would probably be quite a task.
> 
> The one "hack" I can think of would be to treat each core+$es as a machine, 
> and then instead of connecting them with ethernet, connect them with a 
> non-coherent bus. Perhaps something like this could do what you want it to do.
> 
> Andreas
> 
> From: Xiaobin Liu <[email protected]>
> Reply-To: gem5 users mailing list <[email protected]>
> Date: Tuesday, 2 April 2013 15:34
> To: "[email protected]" <[email protected]>
> Subject: [gem5-users] Each Core with private memory
> 
> Hi gem5 team,
> 
> My research is to design and simulate a multicore architecture under mesh 
> topology with each core having its own memory, which cannot be seen by other 
> processing units. Communication is done by interconnection of L1 caches of 
> different cores.
> I find that the memory model is based on one single instance of physical 
> memory at bottom. Although distributed generalized memories are enabled in 
> this way http://reviews.gem5.org/r/1113/diff/?page=3, it seems that no one 
> has done private memory stuff. 
> Thus here comes the question, is it reasonable and feasible to adapt the 
> source code of the interface between NoC and memory to my target 
> architecture? 
> I am a newbie in gem5 and hope it won't bother you. I would appreciate that 
> if anyone kindly gives me a hint.
> 
> Regards,
> -Xiaobin
> 
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