Re: [Qemu-devel] QEMU timing requirements

[address@hidden]

On 06/25/2011 06:26 AM, Mulyadi Santosa wrote:
> On Sat, Jun 25, 2011 at 09:34, address@hidden
> <address@hidden>  wrote:
> > Hello,
> >
> > I am currently implementing some heuristics using a patched qemu
> > (i386-softmmu). Two of them take some time for each vm memory access. If I
> > run them both, suddenly qemu segfaults while executing a BBL. Using just one
> > of them never triggers this problem.
> "Two" instances of Qemu running at the same time, you mean?

No. What I do is using gen_helper_ to compile hooks into call/ret/jmp 
and memory access. The Heuristics can then hook the events so 
calculation is done during the execution of a basic block. I thought 
that it could be possible that Qemu sets a timeout for BBL execution to 
prevent CPU monopolization by e.g. a long sequence of rep. That would 
make sense because my heuristics calculation time falls into the BBL 
execution time for Qemu. Does anyone know more about that?

Regards,
    Felix