[PTLsim-devel] Problems because of setting affinity

Sat Oct 13 18:25:01 EDT 2007

On Saturday 13 October 2007 17:54, Ferad Zyulkyarov wrote:
> Hi,
>
> I run PTLsim in fullsystem mode. I run mutli-threaded applications on
> the simulator and explicitly bind threads to the CPUs by setting the
> CPU affinity because applications that I simulate are small and the OS
> does not schedule the threads to different CPUs.
>
> The problem that I observe is that in certain point the simulation
> stops and the simulator does not simulate/execute any instructions (0
> instructions/second).
>
> Do you have any similar problems, and do you know why does it happen?
>
> We (me and my colleague) suppose that the simulator does not run the
> other VCPUs. And when thread 0 finishes execution it waits on join
> point. But because the other CPUs are not running, they don't execute
> the other threads (1, 2, 3) and the simulation blocks.
>
> When I don't set the CPU affinity everything is fine (unless the
> threads are not assigned to non-running VCPU). This happens with the
> SMT and the sequential cores.
>
> I use code revision 220 (it is a little bit old).
>

Please ask Hui Zeng (hzeng at cs.binghamton.edu) about this. He designed the SMT 
core, and he figured out a way to deal with the affinity problem you 
describe.

- Matt

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 Matt T. Yourst                    yourst at peptidal.com
 Peptidal Research Inc., Co-Founder and Lead Architect
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